The answer that best described the type of cellular transport that the student is investigating would be passive transport of osmosis: The correct option would be D.
To recall: osmosis is simply the movement of water molecules from the region of high water potential to the region of low water potential through a semi-permeable membrane.
From this definition:
The student observed the movement of water molecules from the beaker (high water potential) into the test tube (low water potential). Â Hence, active transport and diffusion are ruled out with osmosis being the only correct option.
More on cell transportation can be found here: https://brainly.com/question/23202309