Stomata is grass leaf are

Explanation :- 

Stomata are minute pores present on the surface of leaves and help in gaseous exchange.

They also control water lost through transpiration.

In plants, stomata are generally of two types:- dumbbell-shaped and kidney-shaped.

In grasses, stomata are dumbbell-shaped.

Final answer :- 

The correct answer is dumb - bell shaped, i.e option (B).