An Assignment of Probabilities to Events in a Sample Space

An assignment of probabilities to events in a sample space must obey which of the following?

A) The probability of any event must be a number between 0 and 1, inclusive.
B) They must sum to 1 when adding over all events in the sample space.
C) They must obey the addition rule for disjoint events.
D) All of the answer options are correct.