单选题 Our planned visit to the United Kingdom ______ because we were unable to get the visas before the date of departure.
A. fell over B. fell down C. fell through D. fell behind

【正确答案】 C

【答案解析】fall over跌倒，摔倒；绊了一跤。fall down跌倒；失败；倒塌。fall through落空；失败。fall behind拖欠；落在后面。