Given a scientific question, generate a correct answer to it.

[EX Q]: Which chemical element is the basis of all life on earth?
[EX A]: carbon

[EX Q]: What is formed when nitrogen and sulfur oxides dissolve in rain?
[EX A]: acid rain

[EX Q]: Bryophyta is the formal taxonomic name for the phylum that consists solely of what?
[EX A]:
mosses