Final answer:
Cells in an unknown solution with an osmolarity of <0.2 Osm would likely undergo hemolysis - swelling up with water and bursting.
Step-by-step explanation:
In an unknown solution with an osmolarity of <0.2 Osm, the cells would likely undergo hemolysis.
When cells are placed in a hypotonic solution with a lower osmotic pressure than the intracellular fluid, the rate of water flow into the cells is greater than the rate of flow out of the cells. This causes the cells to swell and eventually burst. This process is known as hemolysis.
Therefore, the correct answer is (a) hemolysis.