单选题These young trees must&nb

问题补充：

单选题Theseyoungtreesmust.A.look after wellB.be well looked afterC.take good care ofD.be taken good care

答案：

B解析考查被动语态。被动语态的构成是am/is/are+过去分词。These young trees是物作主语，应该用被动语态；must后应该用动词原形，am/is/are的原形是be，排除A、C；D项的固定短语缺少介词of，排除D。“照顾”look after= take care of。故选B。