Which sentence is written in the active voice?
a) my new car was washed by sam.
b) the sweet apple pie was prepared by the chef.
c) my grandmother makes the best fried pies in the state.
d) the jelly and preserves were made by my aunt betty for my birthday.

In the sentences provided above, the one which is in the active voice is:

C) My grandmother makes the best fried pies in the state. 

In active voice, the doer of the action is given more emphasis than the receiver of the action. "My grandmother" is the doer of the action which is followed by the verb "makes".