The concentration of a sugar is high inside a cell and slightly lower outside the cell. what is most likely to occur if the sugar molecules can cross the membrane?
a. sugar molecules move inside the cell membrane.
b. sugar molecules move toward the nucleus.
c. sugar molecules maintain their concentration gradient.
d. sugar molecules move outside of the membrane.

The right answer is d. sugar molecules move outside of the membrane.

The simple diffusion is the diffusion through the plasma membrane (in the direction of the strong concentrations towards the weak concentrations, until equilibrium concentrations on both sides of the membrane). In the case that we have, the most concentrated compartment in glucose (that is inside the cell) will let it escape and go to the extracellular compartments until reaching equal concentrations between the two compartments.