According to p = fs = GS = rhoshgs = rhohg:
The pressure of A on the ground is pA=ρAhg, and the pressure of B on the ground is Pb = ρ bhg;
Pa > Pb, that is ρ ahg > ρ bhg,
∴ρA>ρB,
When the same mass m is cut from the upper parts of two objects in the horizontal direction,
mA=ρASA△hA,mB=ρBSB△hB,
MA = mB = m, and ρ a > ρA>ρB, sa > sb.
∴△hApb′.
So choose a.