Dr. Musca says, "Humans are born with freedom, yet do not 'naturally' strive to reach their full growth potential." The psychological perspective that would MOST closely agree with Dr. Musca's statement would be:

the Humanistic Existential Approach

Explanation: The Humanistic Existential Approach to psychology focuses on the freedom and responsibility we have as humans. When used as a therapeutic method, it aims to understand the client’s unique experiences rather than group them into a bracket defined by pathology. It makes the client aware of the options available to them and aims to develop the self.  

The Humanistic Existential Approach is based on the humanistic approach which believes in viewing the human nature in a positive light and it therefore also emphasizes positive and healthy relationships.