A nurse is teaching a client about family planning using the basal body temperature method. Which of the following instructions should the nurse include in the teaching?

A. “Take your temperature within 30 minutes after your first morning void”: Delaying the temperature reading can introduce external variables that affect accuracy. Activities like walking or urination can raise core body temperature slightly and distort the basal reading. B. “Take your temperature every night before going to bed”: Evening temperatures do not reflect basal body temperature, which must be measured after a period of complete rest. Nighttime readings are affected by daily activities and are not reliable for this method. C. “Take your temperature immediately after waking and before getting out of bed”: Basal body temperature should be taken at the same time every morning before any physical activity to ensure accuracy in detecting ovulation-related changes in body temperature. D. “Take your temperature 1 hour after getting out of bed”: Waiting an hour allows for changes due to movement, eating, and other morning activities, making the reading inaccurate for monitoring the subtle shifts associated with ovulation.