Which approach to defining abnormal behavior is based on the idea that behavior is abnormal if it differs markedly from a society's ideas of proper functioning?

Social norms approach

Social norms approach: Many psychologists have stated that ‘abnormal’ is simply a label that is given to a behaviour which is deviant from social expectations. Abnormal behaviour, thoughts and emotions are those that differ markedly from a society’s ideas of proper functioning. Each society has norms, which are stated or unstated rules for proper conduct. Behaviours, thoughts and emotions that break societal norms are called abnormal.