What level in Maslow's Hierarchy describes the need for shelter and sustenance?

The level in Maslow's Hierarchy that describes the need for shelter and sustenance is indeed physiological needs. This foundational tier encompasses basic requirements for human survival, including food, water, warmth, and rest. These elements are essential for maintaining life and health, making them the most fundamental of human needs. In this context, shelter provides protection from the elements, while sustenance ensures that individuals have the nutrition necessary for their physical well-being.

Other levels of Maslow's Hierarchy, such as security, self-actualization, and self-esteem, build upon these physiological needs. Security refers to safety and stability, self-actualization pertains to the realization of individual potential and personal growth, and self-esteem involves feelings of accomplishment and recognition. However, none of these higher-level needs could be adequately pursued without first satisfying the basic physiological requirements that ensure survival.