单选题 You must complete the enclosed form and return it within 30 days of purchase ______ you may activate the one-year replacement guarantee.
  • (A) what
  • (B) which
  • (C) because
  • (D) so that


【正确答案】 D
【答案解析】空格内应填入引导状语从句的连词，所以在C选项和D选项中选择词义合适，并且能和后面的may搭配的词语。so that..may／can是“以便”的意思。