Which of the following locations provides the least reliable measurement of actual body temperature?

A. Temporal: Temporal artery thermometers provide fairly accurate readings and are non-invasive. They reflect core body temperature closely, though slightly affected by skin perfusion and ambient conditions. B. Axillary: Axillary temperature measurement is the least reliable because it is influenced by ambient temperature, improper placement, and skin surface factors. It often underestimates core body temperature by 0.5–1.0°C compared to oral or rectal readings. C. Oral: Oral temperature measurement is generally reliable if the patient has not eaten, drunk, smoked, or exercised recently. It reflects core temperature reasonably well in cooperative patients. D. Rectal: Rectal measurement is considered one of the most accurate methods for assessing core body temperature, typically 0.5°C higher than oral readings, and is preferred when precise measurement is required.