Reading Comprehension (RC) | Re: Until recently, nearly everyone thought of intelligence as a single en

Someone could enlighten what support the answer B at the question 2?

Until recently, nearly everyone thought of intelligence as a single entity that could be measured by a simple IQ test. In 1983, however, Dr. Howard Gardner, a professor of education at Harvard University, introduced his theory of multiple intelligences. Today, there are two major schools of thought on intelligence. Despite extensive and ongoing research, scientists have been unable to prove definitively one theory