Which Statement Accurately Describes Hormone Level Regulation in the Human

Which statement accurately describes hormone level regulation in the human body?

A) Hormone levels always remain at a certain level without increasing or decreasing.
B) Hormone levels fluctuate as the body releases more hormones if needed.
C) Hormone levels are on a rigid 24-hr schedule that replicates each day.
D) Hormone levels remain constant as long as the temperature inside and outside the body remains constant.