Why Did the University of California at Berkeley Send Out

Why did the University of California at Berkeley send out police to arrest a group of students in the fall of 1964?

A) The students were collecting money for a civil rights organization that registered voters in Mississippi.
B) The students were demonstrating their Second Amendment rights by marching across campus with guns.
C) The students - all of whom were African-Americans - wanted to enroll in the University's engineering program.
D) The students were suspected to have dealt drugs to undergraduates and faculty.