The pilot had been warned about the storm before he . . . . . . . .

took up
took away
took off
took over

The correct answer is C. took off.

The other options are incorrect because:

  • A. took up is not a common idiom for flying a plane.
  • B. took away is not a common idiom for flying a plane.
  • D. took over is not a common idiom for flying a plane.

The idiom “take off” means to start flying. It is often used in the context of airplanes, but it can also be used to describe other types of vehicles, such as cars or boats.