Which one of the following will reduce the rate of transpiration?

Given below are two statements:
Statement $I$: The forces generated by transpiration can lift a xylem-sized column of water over $130 \text{ meters}$ in height.
Statement $II$: Transpiration cools leaf surfaces,sometimes by $10$ to $15$ degrees,through evaporative cooling.
In the light of the above statements,choose the most appropriate answer from the options given below:

The transpiring organ in plants is

Wilting and curling of leaves occur due to which factor?

What will be the effect of water deficit (in soil) on the rate of transpiration?

In darkness,the stomata close because: