[单选题]

It is often difficult to get correct information on campus crime because some colleges 。
A． receive too many visitors
B． mirror the rest of the nation
C． hide the truth of campus crime
D． have too many watchdog groups

It is often difficult to get correct information on campus crime because some colleges 。A． receive too many visitorsB． mirror the rest of the nationC． hide the truth of campus crimeD． have too many watchdog groups