Computer Virus

 

Exercise (Answers)

1. Choose the best answer from the given alternatives. 

a. Which of the following is harmful for computer?

• Antivirus
• Virus👈
• Freeware

b. The computer virus is simply a_________.

• disease
• set of computer instructions and code👈
• type of bacteria

c. Which one is not a computer virus?

• Trojan Horse
• Logic Bomb
• McAfee👈

d. Special program which can detect and remove viruses from computer is called

• Virus
• Antivirus👈
• Groupware

e. Which of the following is a antivirus program?

• Norton
• McAfee👈
• Both i. and ii.

f. Which of the following is a symptom of virus infection?

• Computer will slower than normal time
• Unwanted message appear on the screen
• Both i and ii.👈

2. State whether the given statements are True or False.

a. The computer antivirus is a destructive computer program that can copy itself and infect a computer system. (True)

b. Most of the computer viruses will delete data, overwrite information, display messages, and add itself to other files on computer.(True)

c. The stealth virus is initially embedded in one document or a few documents but it can spread to other documents within the same computer. (False)

d. A file infector virus infects the boot sector on hard disk, floppy disk and also bootable media such as CD and DVD. (False)

e. A stealth virus will be hide itself in system memory in every time a program scanner is run. (True)

f. C-Brain, stone, disk killer, Poly Boot, etc. are the examples of script sector virus. (False)

2. Fill in the gaps with correct words.

a. The computer viruses are small programs that are designed to replicate, attach to other programs and damage and corrupt the computer programs.

b. A macro is a series of commands that automatically triggers a specific function within a software program.

c. File infector virus is a type of computer virus that inserts its malicious code into executable files on a system.

d. If your computer is infected from the virus , your computer will be slow down and do not response properly.

e. To keep your computer safe from the virus attack you always have to use anti virus program on your computer system and update it regularly.

f. Anti virus programs are utility tools used to detect and remove the virus from the computing device.

4. Answer the given questions.

a. Define the computer virus. Write down a few examples of computer virus. 

Ans: A destructive computer virus that can copy itself and infect a computer system is known as the computer virus.
Examples: i. Poly Boot    ii. Cascade    iii. I Love You    iv. Script Virus

b. What are the types of virus? Name them.

Ans: There are mainly 5 types of computer virus which are mentioned below.

1. Macro Virus
2. Boot Sector Virus
3. File Infector Virus
4. Script Virus
5. Stealth Virus 

c. Write about macro virus, script virus and stealth virus.

Ans: 

Macro Virus

    It is a type of computer virus that spreads to other computer through software programs that utilizes macros. It is initially embedded in one document or a few documents, but it can spread to other documents within the same computer.

Script Virus 

    A script Virus is spread through webpages and has several properties such as being easy to program, malicious, and highly transferable. It changes the scripting code in Html document.

Stealth Virus

A stealth virus will hide itself in system memory every time a program scanner is run. It employs various techniques to hide any changes so that when scanner looks for altered sections, the virus redirects it to any area that contains the clean, uninfected data.

d. What are the symptoms of virus infection?

Ans:  The symptoms of virus infection are listed below:

• Computer will be slow down and do not response properly.
• Computer will restart itself.
• Unwanted error message appears on the screen.
• Programs and files may disappears from the computer system.
• Disk and drive may not open properly.
• Antivirus program may not work properly or may disappear from the system 

e. What is the use of antivirus program? Write with examples.

Ans: The major use of antivirus program is to protect the computer system from the computer viruses.

And it further allows us to schedule scans to automatically run and it removes malicious codes that are detected.

Some of the examples of antivirus program are: a. McAfee       b. NOD32         c. Kaspersky                                                                                                d. AVG            e. Norton antivirus 

f. Write down the functions of Antivirus program?

Ans: The major functions of antivirus program are listed below,

• It scans specific files or directories for any malware or known malicious programs.
• It allows us to schedule scans to automatically run.
• It allows us to initiate a scan of a specific file, storage media or computer at any time.
• It removes malicious codes that are detected.

g. Why is it essential to use anti virus software in our computing devices?

Ans: The destructive computer program can copy itself and infect a computing device in an unexpected manner, so it is essential to use antivirus software in order to detect and remove the virus from the computer system.