1. Nuclear energy, (despite) its early promise as a (source of) electrical power, (is still) insignigicant in compared (with) older and safer energy sources.
The answer is D. I'm confused about it.
2.(Melting) glaciers may (account) the rise (in sea level) that (has taken place) during this century.
The answer is B. It beats me
3. Edwin Franko Goldman was the first bandmaster (to encourage) leading contemporary (Compositions) to write (original) works for a (band).
The answer is B.
4. The Gerneral Sherman tree, a (giant) sequoia in California, (has grown) to be the world's (largest) plant at (approximate) 272 feet tall.
The right answer is D, I'm wondering how to corret it.
Thanks a lot! | 
