Which identifies the main purpose of biological taxonomy?

The main purpose of biological taxonomy is to use a systematic method to name, organize, and show relationships among species.

Taxonomy (from Ancient Greek: τάξις taxis, "arrangement", and -νομία -nomia, "method") is the science of defining groups of biological organisms on the basis of shared characteristics and giving names to those groups.

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what? are the statements?

because photosynthesis could not occur (apex)