Around the world, people may experience the same genetically based disorder quite differently, depending on their personal expectations and their cultural definition of abnormality. This BEST illustrates the need for what model?

The answer is biopsychosocial model.

Explanation:

As the name implies, this branch of psychology studies the relation between biological, psychological and social factors, and focuses on how these circumstances affect our development.

In recent years, social factors have had a bigger role in this area. It is used mostly for understanding health and illness.