A person’s basal body temperature is the body temperature measured as soon as they wake in the morning. In women, a rise in blood progesterone concentration leads to a slight increase in basal body temperature. The graph shows the basal body temperature of one woman across a 28-day period. On which day did ovulation take place?
- Aday 1
- Bday 5
- Cday 11
- Dday 27