Final answer:
When fish are present, Daphnia (water flea) will have negative phototaxis as more adaptive.
Step-by-step explanation:
The hypothesis states that Daphnia (water flea) will have negative phototaxis when fish are present because it would be more adaptive. Negative phototaxis is the movement away from light. This behavior is an adaptive response to avoid predators. Fish are visual predators and are attracted to areas where there is light. By moving away from light, Daphnia can reduce their chances of being eaten by fish.