The First,second,and Third Workers Employed by a Firm Add 24,18,and

The first,second,and third workers employed by a firm add 24,18,and 9 units to total product respectively.Therefore,the:

A) marginal product of the third worker is 9.
B) total product of the three workers is 54.
C) average product of the three workers is 18.
D) marginal product of the first worker is 18.