Determine if this passage is an argument or nonargument: Evolution is central to vertebrate biology because it provides a principle that organizes the diversity we see among living vertebrates. Also it helps to fit extinct forms into the context of living species. Classification, initially a process of attaching names to organisms, has become a method of understanding evolution. --F. Harvey Pough, et al., Vertebrate Life, 7th edition Group of answer choices Nonargument Argument; conclusion: It helps to fit ... the context of living species. Argument; conclusion: Evolution is central to vertebrate biology. Argument; conclusion: Classification ... a method for understanding evolution. Argument; conclusion: It provides a principle ... among living vertebrates.