In a Criminal Case, If Evidence Is Not Gathered Properly

In a criminal case, if evidence is not gathered properly, such as by a search that violates Fourth Amendment rights, then at trial that evidence is:

A) allowed to be referred to but not presented directly
B) allowed only if probable cause is first established
C) dropped under the exclusionary rule
D) irrelevant since there can be no trial if there was an improper search
E) none of the other choices