- Cell X is placed in pure water.
- Cell Y is placed in a concentrated salt solution.
Cells are observed after some time. Cell X swells, and Cell Y shrinks.
Which statement provides the correct explanation for the above observations?
(i) Salt molecules moved into Cell Y, causing it to shrink.
(ii) Water moved into Cell X and more water moved out of Cell Y than the salt solution entered in it.
(iii) Water moved into Cell X and moved out of Cell Y through the cell membrane.
(iv) Solute movement caused osmosis in both cells.

Explanation:
(iii) Water moved into Cell X and moved out of Cell Y through the cell membrane.
Reason: The third statement is correct because it valid the process of osmosis. when Cell X place in higher water concentration, the osmosis occurs, because the water concentration of cell X is lower and we know osmosis took place that makes movement of water molecule through selectively permeable membrane from higher concentration to lower concentration that’s make Cell X swell up.
On the other hand, Cell Y shrink because it is placed in concentrated Salt solution that makes lower water concentration. Inside Cell Y water concentration is High as compared to outside solution. That’s makes osmosis process. The water molecule in Cell Y goes to outside the solution which makes Cell Y Shrink.