Which sentence is best as it is?

A. Shawn stayed to watch only a football game; everybody else went out.

B. Only Dave will go with us; the others are busy.

C. Sara drinks only water; she dislikes milk and soda.

D. Leah only studied for the test; the other students forgot.

The sentence that is best as it is is option B: Only Dave will go with us; the others are busy. The rest of the sentences contain incorrect parts such as the proper use of the word "only". In the first sentence, it should be "only to watch". In the third sentence, it should be "only drinks water". In the third sentence, it should be "Only Leah studied".