Dogs and cats must be kept within what ambient temperature range, according to the standards?

The correct range for ambient temperature in which dogs and cats must be kept, according to the standards of animal welfare regulations, is 45°F to 85°F. This range is designed to ensure the health and well-being of these animals by preventing exposure to extreme temperatures that could lead to stress, heatstroke, or hypothermia.

The standards reflect an understanding of the physiological needs of dogs and cats, taking into account their fur coverage, size, and typical environmental adaptations. Maintaining a temperature between 45°F to 85°F helps create a comfortable environment that supports the animals' normal behaviors and activities.

A lower or higher temperature limit, as seen in the other options, would not adequately safeguard the health of dogs and cats. For instance, options that propose ranges outside of these parameters, like 35°F to 90°F or 40°F to 80°F, either expose animals to colder conditions that could jeopardize their well-being or permit exposure to excessively warm conditions, which could lead to overheating. Therefore, the selected range ensures a balance that promotes animal welfare.