Paul, a Police Officer, Is Working as an Undercover Drug

Paul, a police officer, is working as an undercover drug agent. He enrolls in classes at the local university where he meets several students in business administration and invites them to come to his house for a party. No mention is made of any drugs, but he does say he will have a keg of beer. Shortly after his guests arrive, he gets out some marijuana and offers it to the group. All of them refuse except for Sam, who has never tried it before. When Paul encourages Sam to try it and Sam lights up the joint, Paul arrests Sam for possession of a controlled substance. In this case, Sam:

A) is clearly guilty as charged.
B) can raise the defense of entrapment and argue that Paul has enticed him to commit a crime he would not have done otherwise.
C) can use the defense of duress.
D) can use the Fourth Amendment to exclude the marijuana as evidence that has been illegally seized.