please help! what does osmotic pressure mean? why did the dialysis bags gain weight?

10. Why did the dialysis bags gain weight at the end of our dialysis experiments (pick one)? a. The solutes moved via osmosis away from the higher osmotic pressure in the bag. b. The solutes moved via osmosis toward the higher osmotic pressure in the bag c. The water moved via osmosis away from the higher osmotic pressure in the bag. d. The water moved via osmosis toward the higher osmotic pressure in the bag