Which of the following sites is used for temperature measurement?

The oral site is commonly used for temperature measurement because it provides a reliable indication of the body's internal temperature. When the thermometer is placed under the tongue, it allows for a close approximation of core body temperature, which is essential for monitoring and assessing a patient's health.

The sublingual area, where the thermometer is placed, is well vascularized, and it allows for quick and accurate readings. Additionally, oral temperature measurements are relatively easy to perform and are widely accepted in clinical settings.

Other sites such as nasal, palmar, and facial are not standard locations for taking body temperature. The nasal cavity can give an indirect measurement and is generally not used as a primary method in clinical practice. The palmar surface of the hand lacks the appropriate conditions for measuring core body temperature, and facial regions do not provide a consistent or accurate measurement of internal body temperature.