A student prepared three different red blood cell suspensions as follows:

In the scenario you've described, the red blood cells (RBCs) would undergo different changes in volume and morphology based on the osmotic environment of each suspension.

- **Suspension A (normal blood serum)**: This environment is isotonic, meaning that the concentration of solutes outside the RBCs is roughly equal to that inside. The red blood cells would maintain their normal shape and volume in this suspension.

- **Suspension B (10% salt solution)**: This environment is hypertonic, meaning that the solute concentration outside the RBCs is higher than inside. As a result, water will move out of the red blood cells in order to balance the solute concentrations, causing the RBCs to shrink and appear wrinkled (a condition known as crenation).

- **Suspension C (distilled water)**: This environment is hypotonic, meaning that the solute concentration outside is lower than that inside the RBCs. Water will move into the RBCs, causing them to swell and potentially burst (hemolysis).

Given this information, the suspension that would contain red blood cells that appear wrinkled and reduced in volume is **B (red blood cells + 10% salt solution)**.