Nicolas just found a vulnerability on a public-facing system that is considered a zero-day vulnerability. He sent an ema

[answerhappygod]

Nicolas just found a vulnerability on a public-facing system that is considered a zero-day vulnerability. He sent an email to the owner of the public system describing the problem and how the owner can protect themselves from that vulnerability. He also sent an email to Microsoft informing them of the problem that their systems are exposed to.
What type of hacker is Nicolas?

A. Black hat
B. White hat
C. Gray hat
D. Red hat