脑出血病人出现瞳孔不等大，昏迷加深，常提示

A．脑室出血

B．小脑出血

C．合并蛛网膜下腔出血

D．脑疝形成

E．血肿形成

The idea of fish being able to produce electricity strong enough to light a lamp is almost unbelievable, _____ several kinds of fish are really able to do this.

A．therefore

B．and 　　　　

C．then 　　　　

D．but