Answer:
cold dye is more dense than hot dye
Explanation:
An ice cube with food coloring is placed in a glass of room temperature water. Dye begins to drop down from the ice cube to the bottom of the glass due to the difference in the density of dye in cold and hot water.
The behavior of food coloring is caused by the density of cold dye and hot dye. The cold dye is more dense than hot dye and food coloring has a slightly higher relative density, than water, so cold dye drop down from the ice cube to the bottom of the glass.
Hence, the correct answer is "cold dye is more dense than hot dye".