Answer:
None of these are correct.
Step-by-step explanation:
I am guessing they are looking for B. to be the answer, but in order to do that, you must have a subordinating conjunction such as "Because, When, Before, After" which then starts a complete sentence. It most definitely is not A or C, because in order to be compound, it must include a coordinating conjunction. (but, and, for, nor, or, so, yet).