Answer:
d. Guard cells will lost water and the stomata will become narrow.
Explanation:
The swelling and collapsing of guard cells is regulated by water.
When water is available, the guard cells will swell and this will lead to the opening of the stomata. When water becomes unavailable, the guard cells lose water to the surrounding cells and then collapse, leading to the narrowing/closure of the stomata.
If the guard cells are left under the microscope's lam for too long, they will lose water through evapotranspiration, collapse and this leads to the narrowing of the stomatal pore.
The correct option is d.
