Stomata is grass leaf are: Rectangular, Barrel shaped, Kidney shaped, Dumb-bell shaped

Two shapes of stomata have been observed in plants such as kidney-shaped and dumb-bell shaped. Narrow-leaf blade has dumb-bell shaped guard cells or dumb-bell shaped stomata such as in grasses and wheat plant. It is more efficient as it requires less water and solutes for opening. Whereas broad leaf blade has kidney-shaped guard cells or kidney-shaped stomata. Thus, the correct answer is option B.