18. Back from his two-year medical service in Africa, Dr. Lee was very happy to see his mother __________ good care of at home.
A
taking
B
taken
C
take
D
be taken
his mother和take care of是被动关系，用过去分词做宾语补足语，故选项B符合答案。
根据句意：在非洲医疗援助两年回来后，Dr. Lee很高兴看见妈妈被照顾得很好。
不能正确判断语态。