Answer: B. Density
Explanation:
Density is the comparison between the amount of matter contained by an object and its volume.
Mathematically, density is defined as; d = m/v
Where d is density
m is mass
and v is volume.
Dumping the toys in the bathwater is taking advantage of density because foam is generally less dense than water and anything less dense than water will float in water.
So, there will be a separation based on density because the foam alphabet letters will float while the other toys will sink due to the fact that they are denser and heavier than water and their molecules are compact; very close together.