【单选题】

Like the body, the memory improves with use. Unlike the body, the memory can improve with age.

For many years, doctors have been studying the way the brain works. We all know that the brain has two sides, the left and the right. The right side controls the senses (seeing, hearing, feeling, tasting and smelling), and is the creative and imaginative side. The left side of the brain controls our logical thinking. It processes the information which comes in, and puts it into order. We call the left side the "educated" side of the brain and generally, in western societies, people have developed this side of the brain more than the right side.
Scientists believe that our brain will work much more efficiently if both the right side and the left side are developed equally. In many schools today, teachers try to educate the children in such a way that both sides of the brain are useD、This can be done with logical subjects including mathematics and science as well as with creative subjects such as art and literature. The result achieved by students who are educated in this way is usually better than the result of students who are educated in a more traditional way. Traditional teaching tends to exercise the left side of the brain without paying very much attention to the development of the right side.
Great thinkers such asBertand Russell, the philosopher, andAlbertEinstein, the scientist, only in their work, but also in creative and imaginative activities. It was because of their many different interests in life that they were able to achieve the full development of both sides of their brain.
As long asEinstein and Russell lived, their brains functioned efficiently. It was their bodies, finally, which could not go on any longer.
The brain works much more efficiently when ______.
A、both sides of the brain are used equally
B、the left side is fully developed
C、scientists work on it
D、the right side is fully developed