Question

1. nutrients circulate endlessly throughout the environment in complex cycles called

a. eutrophication cycles.
b. respiration cycles.
c. photosynthesis cycles.
d. biogeochemical cycles.

Explanation:

Biogeochemical cycles describe the continuous movement of nutrients through the biosphere, geosphere, atmosphere, and hydrosphere. Eutrophication is related to excessive nutrient - enrichment in water bodies, respiration is related to energy - release in organisms, and photosynthesis is the process of converting light energy to chemical energy.

Answer:

D. biogeochemical cycles