问题补充：
What worried the child most was to visit his mother in the hospital .
A. his not allowing
B. his not being allowed
C. his being not allowed
D. having not been allowed
答案：
A. his not allowing
(答案→)B. his not being allowed
C. his being not allowed
D. having not been allowed
解析：可联系答.案.网客服索取。
