Stomata are the special structure of the plant (leaves) through ehich the teanspiration occurs. Stomata of a plant open due to

1. influx of hydrogen ions
2. influx of potassium ions
3. efflux of hydrogen ions
4. effluc of potassium ions

Hi
The correct answer is (2) influx of potassium ions.
When conditions are conducive to stomatal opening (e.g., high light intensity and high humidity), aproton pumpdrivesprotons(H+) from theguard cells. This means that the cells'electrical potentialbecomes increasingly negative. The negative potential opens potassium voltage-gated channels and so an uptake ofpotassiumions (K+) occurs.