Which of the following is NOT a primary housing requirement?

Providing adequate storage space is often considered a secondary requirement rather than a primary housing requirement. Primary housing requirements for animals typically focus on the immediate needs that contribute to their health, safety, and well-being. This includes aspects such as security from predators, access to clean water, and proper ventilation.

Security from predators is crucial because it protects animals from threats that could cause harm or death. Access to clean water is essential for hydration and overall health, affecting an animal's ability to thrive. Proper ventilation ensures a healthy living environment, preventing issues such as heat stress or respiratory problems due to poor air quality.

In contrast, while having adequate storage space can be important for managing food supplies or equipment, it does not directly impact the immediate well-being and safety of the animals housed. Therefore, it is categorized as less critical compared to the other foundational needs.