Types of Computer Virus: Important Questions, MCQ
1. What type of virus infects the boot sector of floppy disks or the Master Boot Record (MBR) of hard disks?
A. Boot Sector Virus
B. Direct Action Virus
C. Resident Virus
D. Multipartite Virus
Answer: A. Boot Sector Virus
Explanation: Boot Sector Virus is a type of virus that infects the boot sector of floppy disks or the Master Boot Record (MBR) of hard disks. The Boot sector comprises all the files which are required to start the Operating system of the computer. The virus either overwrites the existing program or copies itself to another part of the disk.
2. Which type of virus attaches itself directly to .exe or .com files and enters the device upon execution?
A. Boot Sector Virus
B. Direct Action Virus
C. Overwrite Virus
D. Polymorphic Virus
Answer: B. Direct Action Virus
Explanation: When a virus attaches itself directly to a .exe or .com file and enters the device while its execution is called a Direct Action Virus. If it gets installed in the memory, it keeps itself hidden. It is also known as Non-Resident Virus.
3. Which type of virus saves itself in the memory of the computer and infects other files and programs when its originating program is no longer working?
A. Boot Sector Virus
B. Resident Virus
C. File Infector Virus
D. Spacefiller Virus
Answer: B. Resident Virus
Explanatin: A virus which saves itself in the memory of the computer and then infects other files and programs when its originating program is no longer working. This virus can easily infect other files because it is hidden in the memory and is hard to be removed from the system.
4. What type of virus can attack both the boot sector and executable files of an infected computer?
A. Multipartite Virus
B. Overwrite Virus
C. Polymorphic Virus
D. Macro Virus
Answer: A. Multipartite Virus
Explanation: A virus which can attack both, the boot sector and the executable files of an already infected computer is called a multipartite virus. If a multipartite virus attacks your system, you are at risk of cyber threat.
5. Which type of virus completely removes the existing program and replaces it with malicious code by overwriting it?
A. Resident Virus
B. Overwrite Virus
C. File Infector Virus
D. Spacefiller Virus
Answer: B. Overwrite Virus
Explanation; Overwrite Virus is One of the most harmful viruses, the overwrite virus can completely remove the existing program and replace it with the malicious code by overwriting it. Gradually it can completely replace the host’s programming code with the harmful code.
6. What type of virus creates a modified version of existing programs and infects the system while retaining the original code?
A. Boot Sector Virus
B. Polymorphic Virus
C. Multipartite Virus
D. Macro Virus
Answer: B. Polymorphic Virus
Explanation: Polymorphic Virus Spreads through spam and infected websites, the polymorphic virus are file infectors which are complex and are tough to detect. They create a modified or morphed version of the existing program and infect the system and retain the original code.
7. Which type of virus first infects a single file and then spreads to other executable files and programs?
A. Boot Sector Virus
B. Direct Action Virus
C. File Infector Virus
D. Macro Virus
Answer: C. File Infector Virus
Explanation: File Infector Virus i first infects a single file and then later spreads itself to other executable files and programs. The main source of this virus are games and word processors.
8. What type of virus fills empty spaces in a file with viruses without affecting the file's size?
A. Spacefiller Virus
B. Overwrite Virus
C. Resident Virus
D. Multipartite Virus
Answer: A. Spacefiller Virus
Explanation: Spacefiller Virus is a rare type of virus which fills in the empty spaces of a file with viruses. It is known as cavity virus. It will neither affect the size of the file nor can be detected easily.
9. Which type of virus is written in the same macro language as used in software programs and infects the computer when a word processor file is opened?
A. Boot Sector Virus
B. Polymorphic Virus
C. Macro Virus
D. Direct Action Virus
Answer: C. Macro Virus
Explanation: Macro Virus is avirus written in the same macro language as used in the software program and infects the computer if a word processor file is opened. Mainly the source of such viruses is via emails.
