49. The main point made by the passage is that the human brain.
A)is much inferior to any known computer
B)is infinitely more complex and powerful than any computer
C)is not as complicated and mysterious as has usually been thought
D)reaches its maximum efficiency at the age of three
E) has been entirely reproduced in computer form
50. It is explained in the passage that the efficiency of the computer_______
A)depend on the speed with which the data are collected
B)will soon make it possible for man to be served by robots
C)can best be appreciated in the decision-making positions
D)is the result of its being concentrated on one task at a time
E) depends on sophisticated electro-mechanical interactions