D — this is the nature vs. nurture debate
Sea snails help to keep the algae's population from growing to high. And the algae provides the sea snails with energy from the snails eating it as a food source.
Individuals suffering from congenital analgesia have a shorter life span due to their injuries and secondary infections of injured sites.
Six carbon dioxide atoms plus six water atoms plus sunlight yields to produce glucose and six oxygen atoms. Sunlight is important because it is the main source of ATP (energy) in photosynthesis. Hope this helps!
