If you get seasick easily, you may prepare for boat rides with some medicine and other helpful stuff. Now there's one more remedy: Timing your breathing to control the nauseaing (作呕的) motion. The technique presumably works because it helps control gravity sensors (传感器) in the abdomen (腹部)—a lesser-known input to our fine-tuned balance system.The brain is traditionally thought to sense body position in three ways. The inner ears sense motions of the head; the eyes see where the head is; and tiny sensory organs in muscles and tendons (筋) sense where the rest of the body is. More recently, researchers have realized that sensors in many other parts of the body also play a role: in the abdomen, the lower organs, and even blood vessels. As long as all of these sensors send matching signals to the brain, we feel directed. But if one or two don't match up, the brain gets confused and we become nauseated.Scientists knew the most sickening motions closely match the rate of natural breathing; they also knew that people naturally tend to breathe in time with a motion. In fact, Navy seamen in World War II discovered that they could use certain breathing tricks to combat motion sickness. But no one had ever tested whether breathing out of time with a motion could prevent nausea.1. According to the passage, which of the following helps control gravity sensors in the abdomen?A. Some medicine.B. Our fine-tuned balance system.C. Timing one's breathing.D. The nauseating motion.