What is the core of a stem that stores food and is composed of undifferentiated cells?

The core of a stem that stores food and is composed of undifferentiated cells is known as the pith. The pith consists primarily of parenchyma cells, which are versatile and have large intercellular spaces that aid in storage and transport. These cells are responsible for storing nutrients and water, making the pith an essential part of the plant's central body.

In contrast, the apical meristem is located at the tips of stems and roots and is responsible for the primary growth of the plant, producing new tissues rather than serving as a storage site. The cork cambium is a lateral meristem involved in secondary growth, contributing to the formation of bark, while bud scales are protective structures found at the tips of young shoots and do not have a role in nutrient storage. Thus, the pith is uniquely suited for storing food due to its composition of undifferentiated, adaptable cells.