What does this idiom mean: "Lazy bones"?

[Magomed]

Test No. incompl/inter-25 "Wrapped round her finger", question 10

Hey, get up and do your homework you lazy ..........

(a) bones
(b) bottoms
(c) hips
(d) back

Test No. incompl/inter-25 "Wrapped round her finger", answer 10

Hey, get up and do your homework you lazy bones.

Correct answer: (a) bones

Your answer was: n/a
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What does it mean?
Lazy bones

[Torsten]

lazy person
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