I would say B. Since both are independent clauses and there's no and between them then you would need a semicolon. The other sentences punctuation are wrong.
I hope this helps!
The answer is A - Dad thought we should have hamburgers for the cookout; but Mom wanted chicken. I hope this helped you!
The correct answer is option B, which uses a semicolon properly to connect two related independent clauses without a coordinating conjunction. Options A and C contain punctuation errors, making them incorrect. Option B effectively creates a compound sentence.
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