LEDs have enormous benefits over standard light

[Volcano1985]

LEDs have enormous benefits over standard light bulbs because they're _______ more efficient, come in a range of different colours and have a very long lifetime

A) very
B) a great deal
C) too
D) over
E) about

I think B

[Our Tort System]

Yep, I concur.
"a great deal more efficient" sounds about right to me.
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