—　What made her so sad？

—　_____ she failed in the examination.

A．That

B．Because

C．As

D．Since

长期不正确用眼，会使眼球结构发生变化导致近视眼，以下属于近视眼成因的是

A．眼轴前后径过短

B．眼轴前后径过长

C．晶状体曲度过小

D．晶状体曲度过大