Ahacker subculture that probes computer systems, usually without permission, to find security flaws as an intellectual exercise or public service sometimes call themselves:

A hacker subculture that probes computer systems, usually without permission, to find security flaws as an intellectual exercise or public service sometimes call themselves vulnerability researchers, their job is to look for the weak side of computer systems, with the purpose of looking for information, files or whatever they need, clandestinely.

The correct answer is b