user
There is a bomb in the chamber of a bomber plane.  The bomb is not attached to anything.  The chamber is opened but the bomb doesn't come out.  Why is this?
A: geometry
B: key
C: plane is flying upside down
D: saddle
E: sequence
assistant
<|begin_of_thought|>

Deep Thought is thinking for 7.5 million years.

<|end_of_thought|>

<|begin_of_solution|>

C

<|end_of_solution|>