Task: Class Definition Understanding (ontology: Human_Society/EmotionOntology)

Which of the following definitions best describes 'circadian behavior'?

A. The rhythm of the locomotor activity of an organism during its 24 hour activity cycle.
B. "Endogenously driven roughly 24-hour cycle in biochemical, physiological, or behavioral processes." [GOC:bf]
C. The specific behavior of an organism that recurs with a regularity of approximately 24 hours.
D. "Any process in which an organism modulates its heart rate at different values with a regularity of approximately 24 hours." [GOC:rl]

Answer: The specific behavior of an organism that recurs with a regularity of approximately 24 hours.