Saint Thomas Aquinas studied Aristotle's teaching. Aquinas believed that man did have a soul and focused on understanding man in these terms. Using Aristotle's logic of knowing reality through experiences, Aquinas recognized that man could only know a reality of the material world; reflecting on one's experiences led to a deeper insight of reasoning. Many medieval philosophers agreed with Aristotle's ideas and confirmed that his ideas did not contradict the Bible; so, the philosophers, many of whom were also Church Fathers, merged Aristotle's ideas with Christian principles. This newly created philosophy came to be called Scholasticism. Scholasticism represented the idea of humans using reasoning and inference to analyze their reality.
I: Both hold that humans have a function and that virtue is necessary for its fulfillment. II: Both hold that certain sorts of actions are intrinsically wrong and that we can know that they are by intellectual apprehension and reason. III: Both hold that things have natures, that their natures determine what is good for them and what is bad for them, and that wickedness is contrary to human nature.
It's got to be C because none of the others relate to collaboration, but I'd say if you were unsure about this answer then the only other sensible one could be B, but I'd go with C.