Examination on Computer Studies
Class: JSS 3
Term: Third Term
Time: 1 Hour
Total Marks: 70

SECTION A: OBJECTIVES (40 Marks)
Instruction: Answer all questions.

1. ________ is a malicious program designed to interfere with the normal operation of a computer. (a) Antivirus (b) Computer virus (c) Firewall (d) Operating system
2. Which of the following is a common symptom of a computer virus infection? (a) Faster internet speed (b) System corruption (c) Increased storage space (d) Brighter screen display
3. All of these are types of computer viruses except ________. (a) boot sector (b) executable file (c) document attack (d) hardware failure
4. A virus that attaches itself to the master boot record of a hard disk is called a ________ virus. (a) Trojan horse (b) boot sector (c) logic bomb (d) email
5. Which of these is NOT a common source of computer virus infection? (a) Infected CD-ROMs (b) Legal software (c) Internet downloads (d) Illegal software
6. An example of a virus that waits for a specific condition to be met before activating is a ________. (a) Trojan horse (b) boot sector virus (c) logic bomb (d) document attack virus
7. The main reason for using antivirus software is to ________. (a) speed up the computer (b) detect and remove viruses (c) improve graphics (d) increase RAM
8. Which of these is not a function of antivirus software? (a) Scanning files (b) Deleting hardware (c) Quarantining infected files (d) Updating virus definitions
9. The correct step in protecting your computer from viruses is to ________. (a) never use the internet (b) regularly update your antivirus software (c) always open suspicious emails (d) share infected disks
10. A type of virus that disguises itself as a legitimate program is known as a ________. (a) worm (b) Trojan horse (c) spyware (d) adware
11. One major symptom of a virus infection is when your computer responds ________. (a) quickly (b) slowly (c) normally (d) instantly
12. Viruses spread through email attachments are often activated when the user ________ the attachment. (a) sends (b) deletes (c) opens (d) forwards
13. Norton, Avast, and McAfee are examples of ________. (a) operating systems (b) antivirus software (c) web browsers (d) word processors
14. ________ software helps to protect your computer from malicious programs. (a) Graphics (b) Antivirus (c) Spreadsheet (d) Database
15. When a computer begins to display ________ characters on the screen, it could be a sign of virus infection. (a) normal (b) strange (c) clear (d) standard
16. A computer virus is a type of ________. (a) hardware (b) application software (c) malicious software (d) system utility
17. Which of the following is a way a computer can get infected with a virus? (a) Installing licensed software (b) Opening emails from known senders (c) Using an infected USB drive (d) Browsing secure websites
18. The process of isolating an infected file by antivirus software is called ________. (a) deletion (b) quarantine (c) backup (d) restoration
19. A virus that targets files with extensions like .exe, .com, or .bat is an example of an ________ virus. (a) boot sector (b) document attack (c) executable file (d) macro
20. Logic bombs are designed to activate based on a specific ________ or event. (a) time (b) location (c) user (d) password
21. If your computer is experiencing ________ saving of files, it might be infected with a virus. (a) complete (b) incomplete (c) quick (d) automatic
22. One function of antivirus software is to ________ virus definitions regularly. (a) delete (b) create (c) update (d) ignore
23. A computer virus can lead to the ________ of your system files. (a) protection (b) enhancement (c) corruption (d) organization
24. Which type of virus specifically targets documents like Microsoft Word files? (a) Boot sector virus (b) Executable file virus (c) Document attack virus (d) Trojan horse
25. Downloading files from ________ websites is a common source of virus infection. (a) reputable (b) secure (c) untrusted (d) official
26. The term “malware” is a broad category that includes ________. (a) hardware (b) operating systems (c) computer viruses (d) internet browsers
27. A computer virus is primarily designed to ________. (a) improve computer performance (b) cause damage or disrupt operations (c) increase storage capacity (d) facilitate communication
28. All of these are symptoms of a virus infection except ________. (a) system slowing down (b) strange error messages (c) increased system memory (d) applications crashing frequently
29. What is the purpose of scanning files with antivirus software? (a) To make files load faster (b) To detect and identify potential threats (c) To compress file sizes (d) To change file formats
30. Which of these can be a source of virus if it’s infected and shared? (a) A new keyboard (b) A blank DVD (c) A USB flash drive (d) A clean mouse
31. A virus that remains dormant until a specific action or date is triggered is a ________. (a) boot sector virus (b) Trojan horse (c) logic bomb (d) document attack virus
32. Antivirus software performs ________ to identify known virus patterns. (a) file encryption (b) signature scanning (c) data compression (d) network configuration
33. If a computer system frequently restarts without warning, it could be a sign of ________. (a) low battery (b) virus infection (c) full hard drive (d) internet connectivity issues
34. The spread of computer viruses through email is often due to ________. (a) strong passwords (b) opening attachments from unknown senders (c) using secure email providers (d) sending plain text emails
35. Which of the following is an example of an antivirus package? (a) Microsoft Word (b) Adobe Photoshop (c) Avast (d) Google Chrome
36. A computer virus can replicate itself and spread to other computers. This characteristic is known as ________. (a) encryption (b) polymorphism (c) self-replication (d) compression
37. When an antivirus software removes a virus, it is performing its ________ function. (a) detection (b) prevention (c) removal (d) update
38. ________ software is essential for maintaining the security and health of a computer system. (a) Gaming (b) Antivirus (c) Photo editing (d) Accounting
39. Illegal software, often pirated, is a high-risk source for ________. (a) original applications (b) virus infections (c) system upgrades (d) faster processing
40. Which of these is NOT a primary function of a computer virus? (a) To delete files (b) To corrupt data (c) To enhance system performance (d) To display annoying messages

SECTION B: THEORY (30 Marks)
Instruction: Answer any THREE questions.

Question 1
(a) Define a computer virus. (2 marks)
(b) List and briefly explain two types of computer viruses. (3 marks)
(c) Give two examples of specific computer viruses and describe one characteristic of each. (3 marks)
(d) State two ways a computer virus can spread from one computer to another. (2 marks)

Question 2
(a) Identify four common sources through which a computer can get infected with a virus. (2 marks)
(b) Describe three warning signs that indicate a computer might be infected with a virus. (3 marks)
(c) Explain why opening email attachments from unknown senders is risky. (3 marks)
(d) State two negative impacts of a computer virus on a user’s data. (2 marks)

Question 3
(a) What is antivirus software? (2 marks)
(b) List three examples of popular antivirus software packages. (3 marks)
(c) Explain three functions of antivirus software. (3 marks)
(d) Briefly describe the process of virus detection by antivirus software. (2 marks)

Question 4
(a) Differentiate between a Trojan horse and a boot sector virus. (2 marks)
(b) Explain why using illegal or pirated software is a significant risk for virus infection. (3 marks)
(c) Describe how antivirus software helps in the removal of a computer virus. (3 marks)
(d) Mention two ways to prevent your computer from getting infected by viruses. (2 marks)

Objective Marking Scheme
Question 1 – ✅ (b) Computer virus
Question 2 – ✅ (b) System corruption
Question 3 – ✅ (d) hardware failure
Question 4 – ✅ (b) boot sector
Question 5 – ✅ (b) Legal software
Question 6 – ✅ (c) logic bomb
Question 7 – ✅ (b) detect and remove viruses
Question 8 – ✅ (b) Deleting hardware
Question 9 – ✅ (b) regularly update your antivirus software
Question 10 – ✅ (b) Trojan horse
Question 11 – ✅ (b) slowly
Question 12 – ✅ (c) opens
Question 13 – ✅ (b) antivirus software
Question 14 – ✅ (b) Antivirus
Question 15 – ✅ (b) strange
Question 16 – ✅ (c) malicious software
Question 17 – ✅ (c) Using an infected USB drive
Question 18 – ✅ (b) quarantine
Question 19 – ✅ (c) executable file
Question 20 – ✅ (a) time
Question 21 – ✅ (b) incomplete
Question 22 – ✅ (c) update
Question 23 – ✅ (c) corruption
Question 24 – ✅ (c) Document attack virus
Question 25 – ✅ (c) untrusted
Question 26 – ✅ (c) computer viruses
Question 27 – ✅ (b) cause damage or disrupt operations
Question 28 – ✅ (c) increased system memory
Question 29 – ✅ (b) To detect and identify potential threats
Question 30 – ✅ (c) A USB flash drive
Question 31 – ✅ (c) logic bomb
Question 32 – ✅ (b) signature scanning
Question 33 – ✅ (b) virus infection
Question 34 – ✅ (b) opening attachments from unknown senders
Question 35 – ✅ (c) Avast
Question 36 – ✅ (c) self-replication
Question 37 – ✅ (c) removal
Question 38 – ✅ (b) Antivirus
Question 39 – ✅ (b) virus infections
Question 40 – ✅ (c) To enhance system performance