16. Which punctuation rule is correct? A. If the adverb clause comes at the beginning of the sentence, set off the clause with a
comma.
B. Complex sentences whose adverb clauses come at the end of the sentence never
require a comma.
C. Relative pronouns signal an adjective clause and are always set off with commas.
D. If a clause begins with the relative pronoun that, writers must use the context, or
meaning, of the sentence to decide whether a comma should be used or not.