Answer:
[tex]\boxed {\tt B. \ Isotonic}[/tex]
Explanation:
We can see that the H₂O or water is leaving the cell and entering the cell at the same rate.
An isotonic solution has the same amount of solute outside the cell and solution inside cell. Therefore, when the water moves across the membrane, the water inside the red blood cell does not change.
Therefore, the best answer choice is B. Isotonic
