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What is the scientific term for an organism's regular circadian rhythm?

  1. Photoperiodism

  2. Endothermy

  3. Chronobiology

  4. Phototropism

The correct answer is: Chronobiology

Chronobiology is the scientific term for an organism's regular circadian rhythm. Photoperiodism (A) refers to the response of an organism to the length of day or night. Endothermy (B) is the ability of an organism to regulate its own body temperature. Phototropism (D) is the movement or growth in response to light. While these terms are related to an organism's daily routine, they do not specifically refer to the regular circadian rhythm. Therefore, Chronobiology is the most accurate term for this concept.