Final answer:
The scientist placed the cells in a hypotonic solution, causing water to move into the cells. However, the presence of a cell wall prevented the cells from bursting. Therefore, the chromosomes repelled each other due to the water potential difference.
Step-by-step explanation:
The scientist placed the cells in a solution that had a slightly higher water potential than the cytoplasm. In this case, the solution was hypotonic to the cytoplasm. When a cell is placed in a hypotonic solution, water particles move into the cell. However, in this scenario, the presence of a cell wall counteracts the osmotic pressure, preventing the cells from swelling and bursting. Therefore, option c) Chromosomes repelled each other due to the water potential difference is the most accurate answer.