I would say that the fishes exhibited the greatest diversity (though the brachiopods also had considerable diversity) and mostly were of the ostracoderms (with a platey or shell-like skin and no jawbone) which exhibited many varieties and also the placoderm which had gills, a jawbone and fins so was developing characteristics of modern fish.
Answer:
<em>Geographic isolation</em>
Explanation:
Geographic isolation can be described as a term that describes the model of speciation in which a biological population becomes isolated from other members of the population and can no longer have gene flow with them.
The same scenario of gene isolation is occurring in the species of taods which live at the top of the mountains in southern Arizona. This population has become reproductively isolated fro all other species of toads within the mountain range.
Enzymes are in the Proteins class
What is A B C and D? You have to tell us what the options are so we can answer.