Sister chromatids separate into individual chromosomes in what phase

The two sister chromatids are separated from each other into two different cells during mitosis or during the second division of meiosis!

I am sure that the answer is A.) Hierarchical Classifications. I hope that I'm right because this will affect you instead of me! But just in case, check this website. It says that a major contribution was Hierarchical Classifications before Binomial Nomenclature.

http://education-portal.com/academy/lesson/carolus-linnaeus-classification-taxonomy-contributions-to-biology.html

(copy and paste)