检验二氧化碳是否收集满了，下列操作正确的是（    ）

A．将燃着的木条伸入集气瓶中间

B．将燃着的木条伸入集气瓶底部

C．将燃着的木条平放在集气瓶口

D．将澄清石灰水倒入集气瓶中

It is a shock that a great number of students ______ injured in the earthquake and the number of them ______ 2,000 already.

A．were, have reached

B．were, has reached

C．was, reaches

D．was, have reached