The correct answer is (d.) proteins. Higher organisms use nitrogen to make their protein. Food that is containing protein also involves nitrogen in it. Protein also has amino acids that contain nitrogen in it which is a necessary essential nutrient for the body.
Answer:
The correct option is d (photosynthesis)
Reason:
Photosynthesis and respiration falls in the category of bioenergetics and metabolism, because photosynthesis end product is glucose which is utilized in respiration to produce ATP.
for some reason I can't submit my typed answer but here's the screenshot