Match the List-I with List-II

LIST I (MALWARE TYPES)		LIST II (CHARACTERISTICS)
A.	Trojan House	I.	Propagates copies of itself through a network
B.	Worm	II.	Triggers action when certain condition occurs
C.	Logic Bomb	III.	Hooks standard OS calls to hide the existence of malware
D.	Rootkit	IV.	Contains unexpected covert effort

Choose the correct answer from the options given below.

The correct option is A-IV, B-I, C-II, D-III.

Let us analyze and match each malware type in List-I with its correct characteristic in List-II:

A. Trojan Horse matches with IV (Contains unexpected covert effort):
A Trojan Horse (misprinted as "Trojan House" in the question) is a type of malware that masquerades as legitimate, useful software. Once installed, it performs hidden, unauthorized, or covert actions behind the scenes without the user's knowledge.

B. Worm matches with I (Propagates copies of itself through a network):
A computer worm is a self-replicating malware program. Unlike viruses, it does not need to attach itself to an existing program or host file. It uses computer networks to actively propagate copies of itself to other systems on the network.

C. Logic Bomb matches with II (Triggers action when certain condition occurs):
A logic bomb is a piece of malicious code intentionally inserted into a software system. It remains dormant and undetected until a specific trigger condition is met, such as a pre-programmed date and time, or the deletion of a specific user account.

D. Rootkit matches with III (Hooks standard OS calls to hide the existence of malware):
A rootkit is designed to hide the existence of certain processes, files, or system data from the operating system's standard detection mechanisms. It does this by modifying or "hooking" standard operating system calls, ensuring the malware remains invisible to security software and administrators.

Matching these definitions, we get:
A - IV
B - I
C - II
D - III