A Plant Physiologist Treats a Leaf with Abscisic Acid and Observes

A plant physiologist treats a leaf with abscisic acid and observes that the stomata close.What happened inside the guard cells during the experiment?

A) Abscisic acid influences the movement of sodium ions out of the guard cells.
B) Abscisic acid influences the movement of potassium ions out of the guard cells.
C) Abscisic acid binds carbon dioxide and causes carbonate crystals to block the stomatal opening.
D) Abscisic acid binds with auxins and induces water molecules to exit the guard cells.