Question

An Aristotelian is someone who believes that sense experiences will lead humans to obtain knowledge of ___________________.

Answer 1

An Aristotelian is someone who believes that sense experiences will lead humans to obtain knowledge of *the eternal forms of things*

Answer 2

Philosophy in times of Aristotle embraced what they called "Natural Philosophy"  which preceded "Natural science" (the study of nature before modern science).

Since modern science is the finest path to obtain knowledge about reality, it's fair to say that Aristotelians who are followers of Aristotle and are inspired by his work, covering existence, mind and ethics; believe that sense experiences will lead humans to obtain knowledge of reality. Thereby the (2nd one).