The correct answer is D. Vesalius
Explanation:
Andreas Vesalius was a Flemish scientist and anatomist that lived during the 16th century, considered as the father of modern anatomy. During this life, Vesalius studied anatomy mainly using dissection and observing the tissues, organs, and structures in them, especially those in animals and humans. Also, he used his findings and ideas to create written works that were the base for later studies in anatomy. Besides this, as compound microscopes for studying living organisms had not been created during Vesalius time, he only used regular observations different to other scientists such as Hooke or Malpighi. Thus, it was Vesalius the one that formed his ideas by performing observations without using a microscope.
