Too much smoking and drinking ________ him greatly, which meant bad living habits had an ________

on his health.[ ]

A．affect; effect  

B．affected; effect

C．affected; effects  

D．affect; effects

把一块橡皮擦切去一半，则剩下的半块橡皮擦 [ ]

A．质量减少一半，密度减少一半

B．体积减少一半，密度减少一半

C．质量不变，密度减少一半

D．质量减少一半，密度不变