Critical Reasoning (CR) | Re: Over the last century, paleontologists have used small

+1 for option C. The question asks for the assumption.

The conclusion is - This classification is unjustified.
Why is the conclusion made ? - The specimens used to distinguish eleven of the species come from animals that lived in the same area at the same time.

Ask yourself - What if in a geographical area you find several different species ? Would the conclusion be valid ?

C it is !

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