to be a football player of the school team the boy made up his mind to train even harder

问题补充：

to be a football player of the school team, the boy made up his mind to train even harder.

A. Having not chosen

B. Being not chosen

C. Not having been chosen

D. Having not been chosen

答案：

A. Having not chosen

B. Being not chosen

(答案→)C. Not having been chosen

D. Having not been chosen

解析：句意：没有被选中做校队的足球运动员，这个男孩决定更加努力的训练。这里需要非谓语动词做状语，因为是先没有被选中，然后才下决心，所以用现在分词的完成式，而且否定词not放在非谓语动词前面，所以选C。