∴GA=GB，

Gently put two identical building blocks into containers A and B (the building blocks are floating),

∴GA=GB，

The two containers are regular cylindrical,

The pressure at the bottom of the container is equal to the gravity of its liquid and wood blocks.

∴FA=FB=GA=GB，

(2)∫SA > SB，

∴ Gently put two identical wooden blocks into container A and container B (both wooden blocks are floating), and the liquid level in container B rises greatly.

∴ From p=ρgh, we can know that the pressure at the bottom of container B is strong, that is, Pa < Pb.

So choose a.