We have two different liquids A and B whose relative densities are 0.75 and 1.0 respectively. If we dip solid objects P and Q having relative densities 0.6 and 0.9 in these liquids, then

In a liquid, a solid object will sink if its density is higher than that of the liquid; otherwise, it will float.

R.D. of liquid A = 0.75
R.D. of liquid B = 1.0
R.D. of object P = 0.6
R.D. of object Q = 0.9

Here, P has R.D. less than both the liquids. So, it will float in both liquids.
Q has R.D. more than liquid A, so it will sink in A, but It has R.D. less than liquid B, so it will float in B.

Therefore, P floats in B and Q sinks in A is correct.