user
what starts off on four legs in the morning two legs in the afternoon and three legs at night
A: person
B: limb
C: cut
D: shank
E: stars
assistant
<|begin_of_thought|>

Deep Thought is thinking for 7.5 million years.

<|end_of_thought|>

<|begin_of_solution|>

A

<|end_of_solution|>