An instance of legal hacking is best described by penetration testing for a company. This involves authorized security testing where a company hires professionals to identify vulnerabilities in their systems. The other options can involve legal or ethical ambiguities:
- "Security hacking is very legal" is too vague and does not specify a context.
- "Looking for security risks on a product that is excluded from a bug bounty program" is likely to be unauthorized and potentially illegal.
- "Grey hat hacking" refers to hackers who may operate in legal gray areas, which might not always be considered legal.
Therefore, penetration testing conducted under a legal agreement is the clearest example of legal hacking.