When a Filament of Algae Is Illuminated with Light That

Multiple Choice

When a filament of algae is illuminated with light that is passed through a prism, different segments of algae are exposed to different wavelengths of light. When aerobic bacteria are present, they congregate in highest concentrations in the areas illuminated by the red and blue light. Which of the following statements provides the best explanation for the bacteria congregation in these areas?

A) Red and blue light increase the temperature in these areas.
B) The highest concentrations of oxygen are available in these areas.
C) Bacteria are attracted to red and blue light.
D) Bacteria congregate in areas with relatively low rates of photosynthesis.