Which of the following attack modifies the original message?
A. Active attack
B. Passive attack
C. Thread attackD. Replay attack

An active attack is a network exploit in which a hacker attempts to make changes to data on the target or data en route to the target.
Types of active attacks:
In a masquerade attack, the intruder pretends to be a particular user of a system to gain access or to gain greater privileges than they are authorized for. A masquerade may be attempted through the use of stolen login IDs and passwords, through finding security gaps in programs or through bypassing the authentication mechanism.
In a session replay attack, a hacker steals an authorized user’s login information by stealing the session ID. The intruder gains access and the ability to do anything the authorized user can do on the website.
In a message modification attack, an intruder alters packet header addresses to direct a message to a different destination or modify the data on a target machine.