Motion sickness occurs when the signals your brain receives from your eyes, ears, and body 17 .
答案：(C) do not match
語意「當大腦從眼睛、耳朵、身體接收到的訊號『不一致』時」，do not match 符合，呼應後文解釋大腦收到矛盾訊息造成的困惑；are not regular（不規律）、can hardly move（幾乎不能動）、are rarely cued（很少被提示）都不合。
match 你最熟的是名詞「比賽、火柴」，當動詞時想到的是「配對」，所以 signals do not match 讀起來會怪：訊號怎麼配對？這裡的 match 是不及物動詞，意思是「相符、一致」——兩樣東西擺在一起對不起來，就是 not match。
答案就寫在下一句：when these parts send conflicting information（當這些部位送出互相矛盾的訊息）。conflicting 正是 do not match 的同義改寫。再往下 One part... detects that your body is moving, but the other parts ___，一邊偵測到在動、一邊沒有，這就是「不一致」的具體說明。選項難以取捨時，往下一句找有沒有同義的說法，是克漏字最穩的做法。
are not regular（不規律）講的是頻率或週期，文章談的是內容互相矛盾，不是時間不規律；can hardly move（幾乎不能動）的主詞是 signals，訊號不會「動」；are rarely cued（很少被提示）語意生硬，文章也沒有提到訊號需要被提示。
match（相符、一致）、match A with B（把 A 與 B 配對）、a good match（很相配）、conflicting information（互相矛盾的資訊）、send signals（發出訊號）、be in conflict with（與……衝突）。
If you have ever been sick to your stomach on a rocking boat or a bumpy car ride, you know the discomfort of motion sickness. It can 16 suddenly, progressing from a feeling of uneasiness to a cold sweat. Soon, it can lead to dizziness, nausea, and vomiting.
Motion sickness occurs when the signals your brain receives from your eyes, ears, and body 17 . Your brain doesn't know whether you are stationary or moving when these parts send conflicting information: One part of your balance-sensing system detects that your body is moving, but the other parts 18 . Your brain's confused reaction makes you feel sick. You may experience the discomfort from the motion of cars, boats, or amusement park rides. You may also get sick from playing video games, or looking through a microscope.
You can take some 19 to help avoid the discomfort. If you are traveling, reserve seats where motion is felt the least, such as the front row of a car or forward cars of a train. Looking out into the distance from the vehicle can help 20 . You can also take medicine before your ride to avoid or reduce nausea and vomiting.