Final answer:
The correct approaches developed within the field of Music Therapy (MT) are Nordoff-Robbins and the Bonny Method. These methods are distinct from psychotherapy, behaviorism, Gestalt therapy, and psychoanalysis, which are more general psychological approaches and are not specific to the field of Music Therapy.
Step-by-step explanation:
The question refers to approaches developed within the field of Music Therapy (MT). The correct option from the ones provided would be (a) Nordoff-Robbins and Bonny Method, as these are two well-known approaches within the field of music therapy.
Nordoff-Robbins is an approach that emphasizes the role music can play in the personal development of individuals of all ages and abilities. The Bonny Method, also known as Guided Imagery and Music (GIM), is a form of therapy that uses classical music and imagery to help explore personal growth, consciousness, and transformations.
While psychotherapy and behaviorism are significant approaches in psychology, they are not specific to music therapy. Similarly, Gestalt therapy and psychoanalysis are also psychological approaches that are not specifically tied to music therapy.
The discussion clearly delineates various psychological approaches and theories including the works of Sigmund Freud, Carl Rogers, and B.F. Skinner, which have greatly informed modern psychology and therapy practices, including music therapy.