On Halloween 31 children walked into the principal’s office asking for candy. They can be classified into three types: Some always lie; some always tell the truth; and some alternately lie and tell the truth. The alternaters arbitrarily choose their first response, either a lie or the truth, but each subsequent statement has the opposite truth value from its predecessor. The principal asked everyone the same three questions in this order.

Are you a truth-teller? The principal gave a piece of candy to each of the 22 children who answered yes.

Are you an alternater? The principal gave a piece of candy to each of the 15 children who answered yes.

Are you a liar? The principal gave a piece of candy to each of the 9 children who answered yes.

How many pieces of candy in all did the principal give to the children who always tell the truth?

**Answer Choices**

A. 7

B. 12

C. 21

D. 27

E. 31