Which of the following best illustrates a pair of sentences that are joined by an understood relationship?
A. Luke put three dollars into the office football pool. He was looking forward to vacation. B. I don't understand a word you said. Have you taken a course in English literature? C. Detective Smiley scanned the dim hallway. He pulled his pistol from its holster. D. It rained for ten days and ten nights. Grandmother Grady called a company to drill a well.