单选题 They found at last ______ they had been looking for.
  • A) that
  • B) what
  • C) where
  • D) which


【正确答案】 B
【答案解析】[解析] “what”在它引导的宾语从句中作介词for的宾语。“that”在从句中不作成分，“where”指地点，故选 B。