Parents should be ____________ in the way they teach their children, so that the children know how to do.       

A．compulsory

B．complex

C．convention

D．Consistent

放射性胃肠道损伤的主要临床表现有（）

A.腹痛

B.腹泻

C.恶心和呕吐

D.便血

E.胸痛