For centuries, people on sea voyages washed their clothes by placing the dirty laundry in a strong cloth bag, then toss it overboard, and let the ship drag the bag for hours.
For centuries, people on sea voyages washed their clothes by placing the dirty laundry in a strong cloth bag, then toss it overboard, and let the ship drag the bag for hours. A. then toss it overboard, and let B. then toss them overboard, and they let C. tossing it overboard, and letting D. tossing them overboard, and let E. tossing it overboard, and let 正确答案是C,我选的D,their clothes不是应该用them指代么?