请教一道语法题，谢谢

请教一道语法题：

According to analysts, an alliance between three major personal computer companies and most of the nation's bargest local telephone companies would enable customers to receive internet data over regular telephone lines with speeds much higher than is currently possible.

有两个选项实在分不清楚

D：at much higher speeds than that

E：at speeds much higher than are

答案是E，为什么不出的是are 啊？

谢谢各位。