A student is investigating cellular transport. They fill a beaker with 250 ml of water. The student then places 10 drops of red food coloring into the beaker of water and makes an observation immediately, after 5 minutes, and after 30 minutes. The student's set up is shown. The student observes that the molecules of red dye move from an area of higher concentration to an area of lower concentration until equilibrium is reached. Which BEST describes the type of cellular transport that the student is investigating?
A.
The student is investigating the active transport of diffusion.
B.
The student is investigating the active transport of osmosis.
C.
The student is investigating the passive transport of osmosis.
D.
The student is investigating the passive transport of diffusion.