The correct answer is B. The wind whipped the branches into a frenzy until it looked like the tree was doing a crazy dance.
Step-by-step explanation:
A subordinating conjunction is a word mainly use to link dependent clause, which is an incomplete idea that requires another sentence to exist, to an independent clause which expresses a complete idea; subordinating conjunction include words as before, therefore, while, even if, so that and until. Additionally, according to grammar if subordinating conjunction is placed in the middle of a sentence it is not required to use a comma before the conjunction. Considering this, the most appropriate revision that uses a subordinating conjunction is "The wind whipped the branches into a frenzy until it looked like the tree was doing a crazy dance" because it uses a subordinating conjunction that is "Until" and there is no comma or any punctuation mark to join the two clauses or before the subordinating conjunction, which is the correct way according to grammar.