问题补充：
Meng Peij ie，an ordinary girl who was among the 10 people awarded the title of “Touching China ”，must be both optimistic and strong-minded. Otherwise, she her disabled adoptive mother for 12 years.
A. mustn have looked after
B. can have looked after
C. couldn have been looking after
D. shouldn have looked after
答案：
A. mustn have looked after
B. can have looked after
(答案→)C. couldn have been looking after
D. shouldn have looked after
解析：本题考查虚拟语气。结合后半句句意“否则，她不可能照顾她残疾的养母”可知此处是与过去相反的虚拟语气。
