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.
The best option to use a semicolon is C , as it consists of two independent clauses that can be connected. A semicolon can clarify the relationship between Jerry's love for tennis and his daily practice. Options A, B, and D do not have two independent clauses suitable for semicolon use.
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