单选题 Immediate solution should be ______ to save the people from the flood that has swept southern China this summer.
A. called at B. called for C. called on D. called in

【正确答案】 B

【答案解析】call at意为“访问，拜访”；call for意为“需求，要求”；call on意为“拜访，号召”；call in意为“收集，邀请”。所填之词的宾语是immediate solution(即刻的解决办法)，所以应该选用call for。