Intelligence or IQ of a person is dependent on his genetic background.
Step-by-step explanation:
Sir Arthur Jensen was a great psychologist of America. He was popular for his studies on genetics and intelligence of human population. He did a research in his lifetime on the relationship between the Intelligence Quotient and the genetic background of the person.
And this resulted in a result which showed that about 80% of the variation in IQ of a population is dependent on the genetic background. Rest 20 % is dependent on several factors like surrounding behavior, economic background, literacy etc.