Which of the following best describes the purpose of the USDA?

The purpose of the USDA, or the United States Department of Agriculture, is primarily focused on overseeing food safety and agriculture. This includes developing policies related to farming, forestry, and food production, while also ensuring that food is safe for consumption. The USDA plays a crucial role in establishing guidelines for the proper handling and inspection of food products, which helps to protect public health. Additionally, the department supports agricultural production, provides financial assistance to farmers, and promotes agricultural research to improve farming practices and food security.

The other options, while important in their own right, do not align with the primary responsibilities of the USDA. Regulating health care facilities is managed by health departments and related agencies. Managing water resources falls under the purview of environmental agencies and water management organizations. Controlling environmental pollution is the role of the Environmental Protection Agency (EPA) and not directly related to the USDA's mission. Thus, the focus on food safety and agriculture is what clearly defines the work of the USDA.