Answer:
The correct answer is C) wavelength of light and rate of photosynthesis.
Step-by-step explanation:
The given question is a famous experiment conducted by T W Engelmann which is called the action spectrum experiment. In this experiment when light passes through a prism it splits into its constituent colors splits into violet, indigo, blue, green, yellow, orange and red.
Aerobic bacteria require oxygen for their survival. The green algae produce oxygen during photosynthesis. Engelmann released aerobic bacteria to it. it is found that the bacteria accumulated at the blue and red light because photosynthesis and oxygen release were higher there. So, it establishes the relationship between the wavelength of light and photosynthesis.