In scotoactive opening of stomata,they remain open during

Accessory cells of stomata are reservoirs of . . . . . . .

In summer months,the rate of transpiration is lowest at

$A$ are structures present in the epidermis of leaves. They regulate the process of transpiration and $B$ exchange. It is composed of two bean-shaped cells known as $C$ cells.
Choose the correct combination of $A, B$ and $C$ from the following options:

What causes the opening of stomata in plants?

Stomatal movement is not affected by