Direct object is D. A NOUN, PRONOUN, OR WORD GROUP THAT RECEIVES THE ACTION OF THE VERB.
Direct object follows a transitive verb (action verb) not a linking verb. It is always placed after the verb not before it. It receives the action not modifies the action verb.
Whitman celebrates the common person.
The answer is: it is about evolution.
Darwin himself characterized his seminal book, <em>On the origin of the species, </em>as “one long argument”. There is still debate as to what exactly did he mean by that characterization, but it is agreed upon that he evidently was referencing his theory of evolution based on common ancestry between species and natural selection as the process of differentiation between them, which, all in all, tells a story that took millions of years, or, in more poetic terms, it summarizes a very long argument.
The answer to this is reins, it is reins because this is all filler for you to allow me to put down this answer, its reins.