Which of the following can lead to an increase in body temperature?

The option that indicates exercise and hormonal changes as factors that can lead to an increase in body temperature is accurate. During physical activity, the body generates heat as muscles work harder, which naturally raises body temperature. This process is known as thermogenesis. Additionally, various hormonal changes, such as those occurring during the menstrual cycle or the body's response to stress through the release of adrenaline and other hormones, can also elevate body temperature. Hormones regulate many body functions, including metabolism, which directly influences heat production.

In contrast, age and sleep generally do not lead to an increase in body temperature; rather, they can affect temperature regulation in other ways. Cold environments typically cause a decrease in body temperature because the body loses heat to the surroundings. Low humidity levels can alter the body’s ability to cool itself, but they do not directly raise the core temperature.