A nurse is preparing to measure the temperature of an infant. Which of the following actions should the nurse take?

Rationale: A. Insert the oral thermometer in front of the infant's tongue: Oral temperature measurement is not appropriate for infants due to the risk of injury and their inability to hold the thermometer properly. It is generally reserved for children older than 4–5 years. B. Pull the pinna of the infant's ear forward before inserting the probe: When using a tympanic thermometer for infants under 3 years, the correct method is to pull the pinna down and back, not forward, to straighten the ear canal. C. Insert the probe 3.8 cm (1.5 in) into the infant's rectum: This depth is too invasive and risks rectal perforation. For infants, rectal insertion should be only 1.5 to 2.5 cm (0.6–1 in), with extreme caution. D. Place the tip of the thermometer under the center of the infant's axilla: Axillary temperature is the safest and most noninvasive route for infants. Ensuring full skin contact under the center of the axilla provides the most accurate axillary reading.