"at speeds much higher than are"

[AmandaS355]

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

A. with speeds much higher than is
B. with speeds that are much higher than are
C. at much higher speeds as are
D. at much higher speeds than that
E. at speeds much higher than are

the answer is E.

A,B "with speeds" is incorrect
C "higher as" is incorrect, it should be "higher than"

BUT D & E really confuse me!!!!
is D wrong just because "that" should be changed into "those"??

and E what is the omitted element?

plz!!help me with it!! thank you sooo much!! ;)))

[RonPurewal]

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