If it is April, then there are 30 days in the month.
Which statement is logically equivalent to the above statement?
a. If there are 30 days in the month, then it is April.
b. If it is not April, then there are not 30 days in the month.
c. If there are not 30 days in the month, then it is not April.
d. If it is April, then there are not 30 days in the month.
