Which of the following is a legitimate criminal procedure?
A. The police tell a suspect that they'll let him call his lawyer after he has cooperated with their questioning.
B. The defendant must call witnesses at trial to prove her innocence.
C. The police get a warrant before arresting a suspect based on the testimony of witnesses to the crime.
D. A defendant who takes the witness stand must confess if the prosecutor asks directly, "Did you do it?"