If It Rains 21 of 30 Days in a Month

If it rains 21 of 30 days in a month, what value represents the probability of rain occurring on a single day chosen at random from the month?

A) 21/30 = 0.70
B) (30 - 21) /9 = 1
C) 30/21 = 1.43
D) (21 + 30) /21 = 2.43