Which of the following is NOT a function of the stem in plants?

The function of anchoring the plant in the ground is primarily attributed to the roots, not the stem. Roots are specialized structures designed to absorb water and nutrients from the soil while securing the plant in place, allowing it stability and access to resources.

On the other hand, the functions associated with the stem include serving as a conduit for nutrients and water, typically through a vascular system, and providing structural support to ensure that leaves and flowers are positioned to maximize photosynthesis and reproduction. Stems can also act as storage organs in some plants for water and nutrients, thus fulfilling several essential roles. Hence, while stems contribute to a plant's overall health and functionality, anchoring is not among their primary responsibilities.