Afood storage area in both the roots and stems is called the
cortex
pith
cuticle
xylem

cortex

Here the answer is cortex.

To define, cortex is where the nutrients collected and process by the plant is located and reserved. Cortex is a significant area in most plants because it acts as a reservoir for food and other needed nutrients when the plants is undergoing cellular processes and other photosynthetic-like functions.