Over 90% of the world's biomass is in

A. Tropical rain forests

B. Freshwater wetlands

C. Top soils

D. Oceans

Note: Over 90% of the world's biomass is in Tropical rain forests. Tropical rainforests are the most complex of the world's ecosystems in terms of the physical structure that they develop, and also in their tremendous biodiversity of species and community types. Because of these characteristics, tropical rainforests represent the acme of ecosystem development on Earth.