Questions 11 to 13 are based ore the following
passage. At the end of the passage, you will be given 15 seconds to answer the
questions. Now listen to the passage.
Why did human beings begin to grow crops and raise livestock
A．Because they wanted to stay in a fixed place. B．Because the foods obtained by hunting were not enough. C．Because those food were more delicious. D．Because their became more and more intelligent.