Biology · Animal Behaviour

Male crickets call at dusk when the light intensity falls below a certain threshold. In a laboratory experiment, these insects were monitored under two light regimes: i) constant light condition for 24 hours (LL) and ii) a 12-hour Light and 12-hour Dark cycle (LD). Consider the following inferences regarding the circadian control of calling activity in these animals: A. Calling activity under LL exhibits a free-running rhythm, whereas under LD it shows an entrained cycle. B. Calling activity under LL represents an entrained cycle and under LD represents a free-running cycle. C. The circadian control of calling activity is driven entirely by endogenous components. D. The circadian control of calling activity is driven entirely by exogenous components. E. The circadian control of calling activity involves both endogenous biological clocks and exogenous environmental cues. Which one of the following options provides all correct statements about the inferences drawn from this experiment?