Question #N445

The word "which" is used in this sentence to connect two independent clauses. The first clause states that "the cat jumped on the table." The second clause states that "the cat knocked over a vase." What is the purpose of the comma in this sentence?

The comma in the sentence is used to
A. separate the two independent clauses.
B. indicate a list of items.
C. introduce a quote.
D. set off a nonessential phrase.