Nowadays, children are ________ too many violent online games, which is bad for the development of their characters.

A．defeated by

B．limited to

C．handled by

D．exposed to

人体实验道德原则不包括的是（）

A.不告知原则

B.医学目的原则

C.维护受试者利益原则

D.知情同意原则

E.科学性原则