Which of the Following Could Be Considered the Most Recent

question 28

Multiple Choice

Which of the following could be considered the most recent common ancestor of living tetrapods?

• A) a sturdy-finned, shallow-water lobe-fin whose appendages had skeletal supports similar to those of terrestrial vertebrates
• B) an armoured, jawed placoderm with two pairs of appendages
• C) an early ray-finned fish that developed bony skeletal supports in its paired fins
• D) a salamander that had legs supported by a bony skeleton but moved with the side-to-side bending typical of fishes

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