meaning of "Take a rest"

[Udai]

Test No. incompl/inter-21 "The two Butter Frogs", question 5

They found plenty of food and decided to stop and ..........

(a) take rest
(b) take a rest
(c) take resting
(d) take rested

Test No. incompl/inter-21 "The two Butter Frogs", answer 5

They found plenty of food and decided to stop and take a rest.

Correct answer: (b) take a rest

Your answer was: incorrect
They found plenty of food and decided to stop and take rest.
_________________________

Why is not "take rest" without the article "a"?

Udai

[Torsten]

It's the same pattern like

take a break
take a decision
take a trip

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