Questions 14 to 16 are based on the
following passage. At the end of the passage, you will be given 15 seconds to
answer the questions. Now listen to the
passage.
The case history of tile twirls appears to support the conclusion that
A．individual with identical brains seldom test at the same level. B．an individual’s intelligence is determined only by his environment. C．lack of opportunity blocks the growth of intelligence. D．changes of environment produce changes in the structure of the brain.