For many years people have wondered ______ exists elsewhere in ...

★ Adverb and Noun Clauses

For many years people have wondered ______ exists elsewhere in the universe.

A. that life

B. life which

C. whether life

D. life as it

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…………..added to a liquid, antifreeze lowers the freezing temperature of that liquid.

A. That

B. As is

C. It is

D. When