The answer is D. A compound sentence requires at least two separate clauses that contain related ideas. These independent clauses can be joined using a coordinated conjunction - for, and, nor, but, or, yet, so- or by the use of semicolons.
<span>A. The local police asked the F.B.I. to assist with the case.
-F.B.I isn't properly punctuated, as there's a period after 'F.B.I', which implies the sentence ends there.</span>
B. Mary remembered to buy milk didn't she?
-Should be 'Mary remember to buy milk, didn't she?'
C. Mr. Jones visited the YMCA before becoming a member.
-This is correct
<span>D. The company held it's annual party at the convention center.</span>
-It's isnt proper, It's is basically 'it is', The company held it is annual party at the convention center obviously does not make sense.
Your answer is very correct
