A Backward Child Is A Slow Learner. He Does Not Respond Satisfactorily To The Ordinary School Curriculum And To The Usual Methods. The Causes Of This Phenomena Are

A Backward Child Is A Slow Learner. He Does Not Respond Satisfactorily To The Ordinary School Curriculum And To The Usual Methods. The Causes Of This Phenomena Are Options: A) Poor Intellectual Ability And Low Intelligence B) Physical Defects And Diseases C) Emotional Disturbance D) All Of The Above