An Officer Stops an Individual for the Purposes of a Terry

An officer stops an individual for the purposes of a Terry stop; he has reasonable suspicion to do so.During the frisk, he finds a small handgun, for which the person has a valid license to own and permit to carry.He also finds a small baggie of cocaine.Can he seize the cocaine and use it as evidence at trial?

A) Yes, he legally discovered the cocaine during the frisk.
B) Yes, according to the "plain feel" rule it is admissible.
C) No, he did not have justification for the stop.
D) No, a Terry stop is allowed to search for weapons only.