Darwin's theory of evolution has 2 parts. what are they?

Ineed to know why d is the correct answer asap

Identify the various levels of atmosphere. troposphere mesosphere exosphere stratosphere thermosphere

Select the true statements about eubacteria. most live as decomposers and heterotrophs. most only thrive in a narrow range of environments. certain eubacteria are responsible for food poisoning. eubacteria thrive in extreme environments.