(20 12? Taizhou) Photographers captured an interesting scene (pictured): a crow resting on the back of a flying eagle. The following statement is correct.

A, the crow stands on the back of the flying eagle to rest. Crow and eagle are relatively static, so taking crow as reference, eagle is static, so this option is correct;

B, the eagle catches the crow and flies, so the ground is taken as the reference, and the crow is moving, so this option is incorrect;

C. The crow stands on the eagle's back to rest. Although it is stationary relative to the eagle, it is moving relative to the ground, so it also has kinetic energy, so this option is incorrect;

D, the eagle can fly in the air mainly because the force is mutual, not buoyancy, so this option is incorrect.

So choose a.