前者是物理变化，后者是化学变化的一组是

A．水结成冰夏日阳光下车胎爆炸

B．酒精挥发酒精燃烧

C．铁生锈电灯通电发光

D．光合作用人的呼吸

—I’m not good at playing football. What should I do?

—You need more ______. The more you play, the better you play.

A．support

B．rest

C．practice

D．humour