Which is not a prepositional phrase in the following sentence?

Under a time restraint, I was able to solve the puzzle before all the others.

A. I was able to solve
B. under a time restraint
C. before all the others

Respuesta :

The answer is:  [A]:  I was able to solve .
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Note: A 'prepositional phrase' ALWAYS begins with a preposition.

Answer choice: [A] — "I was able to solve"—is the only answer choice given that does not begin with a preposition.
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