ANSWER: BOT
EXPLANATION: When a PC is experiencing the listed effects, it thus depicts that the PC is under attack by a bot, which is a type of script or software application that establishes automated tasks via command.
However, a bad bots often initiate malicious tasks that gives room for attackers to take control over an affected PC remotely, most especially for fraudulent activities.
When several affected computers are connected, they form a botnet connection.