What does this phrasal verb mean: 'take off'? Is it an idiom?

[yee]

Test No. incompl/inter-30 "Flying on a Plane", question 1

The worst thing about flying is when you take ..........

(a) up
(b) in
(c) off
(d) over

Test No. incompl/inter-30 "Flying on a Plane", answer 1

The worst thing about flying is when you take off.

Correct answer: (c) off
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The worst thing about flying is when you take.....
answer: up

[Alan]

This phrasal verb is used to describe a plane leaving the ground and going up into the air.
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