单选题 The greatest obstacle to mechanization is the fear in underdeveloped countries ______ the workers who are displaced by machines would not find work elsewhere.

A. that
B. where
C. as
D. for

【正确答案】 A

【答案解析】that引导fear的同位语从句，说明fear的内容，其他连接词都不符合逻辑。句意为：“机械化最大的障碍是人们担心不发达国家中被机器取代了的工人找不着工作。”