In which one of the following sentences could you best use a semicolon?

A If you ask me Jerry is a tennis whiz.

B When she is worried Lucille eats a lot.

C Jerry loves tennis he plays everyday.

D Lucille bought a new tennis racket and brought it home.

I think it's C.

Because, lemme put commas on each sentences ...

(1) If you ask me, Jerry is a tennis whiz.

(2) When she is worried, Lucille eats a lot.

(3) Jerry loves tennis, he plays everyday.

(4) Lucille bought a new tennis racket and brought it home. << Where should I put it?

So, (4) is automatically out of question. (1) and (2) seems okay with comma, but (3) is a little bit weird. (3) supposed to have 'and' in the middle, but it's not there. So, you can put semicolon there, to separate the words.