Which statement about basal body temperature is true?

• A. The normal range is 97.6 to 98.2°F.
• B. The normal range is 95.0 to 96.0°F.
• C. The normal range is 99.0 to 100.0°F.
• D. Basal body temperature is not used in clinical assessment.

Answer: (A)

Basal body temperature reflects your resting body temperature first thing in the morning. Around ovulation, progesterone causes a small rise in this temperature, typically about 0.4–0.8°F, and it stays higher until your next period. The range around 97.6–98.2°F lines up with what many people experience after ovulation in a normal cycle, so saying this is the normal range is accurate. To observe this pattern, you measure your BBT with a basal thermometer first thing after waking, every day, before any activity, and track the shifts across the cycle. This tool is mainly used for fertility tracking rather than broad clinical diagnosis.