While taxonomic classifications can vary, in the context of comparing these groups, Algae are overwhelmingly found in aquatic environments (freshwater, marine, brackish). Bryophytes are primarily terrestrial but require moist habitats and water for reproduction. Pteridophyta (ferns) are also mostly terrestrial, although some species are aquatic. Gymnosperms (like conifers) are exclusively terrestrial plants. Therefore, Algae represent the group that is predominantly aquatic.