Four People Have Just Observed a Suspect Deny That She

Four people have just observed a suspect deny that she committed a theft.Which observer is most likely to detect whether the suspect is lying?

A) Frank,who is a rookie on the police force
B) Alice,who has just taken a social psychology class.
C) Andy,who has worked for the Secret Service
D) Bobby,who is visiting the police station as part of a university assignment
E) None of the above observers has an edge in detecting lies.