It Is a Fact That Major Life Forms Now on Earth

Multiple Choice

It is a fact that major life forms now on earth were not at all represented in the past. There were no birds or mammals 250 million years ago. It is a fact that major life forms of the past are no longer living. There used to be dinosaurs and Pithecanthropus, and there are none now. It is a fact that all living forms came from previously living forms. Therefore, all present forms of life arose from ancestral forms that were different: birds arose from nonbirds and humans from nonhumans. R.C. Lewontin, "Evolution/Creation Debate: A Time for Truth"

A) Argument; conclusion: It is a fact that all living forms ... previously living forms.
B) Argument; conclusion: It is a fact that major life forms of the past are no longer living.
C) Nonargument.
D) Argument; conclusion: It is a fact that major life forms ... represented in the past.
E) Argument; conclusion: All present forms of life ... forms that were different.