At five she was by her mother who was a famous dancer when young to go into training.A.

问题补充：

At five she was by her mother, who was a famous dancer when young, to go into training.

A. led

B. enjoyed

C. imagined

D. forced

答案：

A. led

B. enjoyed

C. imagined

(答案→)D. forced

解析：句子的主干是：At five she was by her mother to go into training.