The Rule of Four Means That

The rule of four means that

A) at least four law clerks must read a case prior to a writ of certiorari being issued.
B) at least four justices must be present at a hearing in order for a decision to be viable.
C) at least four justices must vote to hear a case and grant the petition for a writ of certiorari for a case to be reviewed.
D) at least four hearings must be held in the lower courts before the Supreme Court can review a case.
E) at least four votes must be taken before a final answer can be arrived at in the Supreme Court.