You are curious whether or not the following two events meet the standard criteria in statistics for mutually exclusive events: January sales exceeding $1 million
February sales exceeding $1 million

Which of the following conditions alone would guarantee that those two events are mutually exclusive?

a. Sales each month are statistically independent of each other.
b. Sales each month are not statistically independent of each other.
c. Available inventory prevents sales for January and February combined from exceeding $1.5 million.
d. In any given month the probability of sales exceeding $1 million is less than 50%. The expected sales in January is more than the expected sales in February.
e. None of the above.