The correct option is(3) O2 concentration
Explanation:
Stomatal movement is not affected by O2 concentration. Stomata are tiny pore complexes found in the epidermis of leaves and other soft aerial parts. They are meant for the gaseous exchange but are also the main source of transpiration. Stomatal movements are affected by many factors like light, temperature and CO2 concentration, In the majority of plants, the stomata are open in light and close in darkness. Normally high temperature above 30oC reduces stomatal opening in many species. Low CO2 concentration usually induces opening of stomata while high CO2 concentration closes the same.
