You Observed That Event a Occurred Before Event B

Multiple Choice

You observed that event A occurred before event B.Which of the following statements is false?

A) Another reference frame must exist in which event A precedes event B.
B) A reference frame must exist in which event B precedes A.
C) A reference frame could exist in which the events are simultaneous.
D) A reference frame could not exist in which event B precedes event A.
E) None of these statements is false.