The in the root is a single layer of cells sandwiched between the cortex and the stele. This layer acts as a selective barrier that regulates the passage of substances from the soil to the vascular tissue

Endodermis

Explanation:

The endodermis is the layer of cells formed around the vascular bundle in plants with vascular bundles and attain a cylindrical shape.

The endodermal cells are barrel-shaped in structure and have a special layer of a hydrophobic molecule called suberin. The suberin gets deposited around the cell wall and in the gaps between the cell which stops the flow of solvent or solute through apoplast.

The suberin layer in the endodermal cells is known as the Casparian strip. This Casparian strip controls the movement of the solution to the vascular bundle.

Thus, endodermis is the correct answer.

i think its c. amphipod