Which of the following best illustrates a pair of sentences that are joined by an understood relationship? a. it rained for ten days and ten nights. grandmother grady called a company to drill a well. b. detective smiley scanned the dim hallway. he pulled his pistol from its holster. c. i don't understand a word you said. have you taken a course in english literature? d. luke put three dollars into the office football pool. he was looking forward to vacation. 17