Answer: c. it will contract
Step-by-step explanation:
An Erythrocyte is a Red Blood Cell and like all cells, when put in a Hypertonic solution (solution with a higher concentration of solutes than the cell) it will undergo a process known as Crenation.
Crenation occurs when due to Osmosis, water particles move out of the cell and into the solution because the solution is more concentrated with solutes than the cell. This causes the cell to SHRINK or CONTRACT.
I have attached a diagram to further describe it.