Identify $X$ in the given figure of a maize grain.

Single shield-shaped cotyledon of a maize seed is called$:-$

The shield-shaped cotyledon is known as:

In cereals,the cotyledon is called:

$A$ type of seed germination in which the epicotyl region of the embryo elongates rapidly to pull the plumule out of the soil surface is called . . . . . . germination.

After germination of a dicotyledonous endospermic seed,the cotyledons act as . . . . . . organ.