With the help of high technology, many new substances（物质）______in the past years.

A．discovered

B．have discovered

C．had been discovered

D．have been discovered

情感对于情绪来说具有的特点是

A．强烈而冲动

B．伴有明显的行为变化

C．伴有明显的生理变化

D．稳定而深刻

E．带有明显的情境性