单项选择题
A．country life is peaceful but dull B．people living in big cities are easy to get excited C．few Americans go to church on Sundays now D．Americans tend to be rough and impolite today
A．Because American people do not like to talk to each other. B．Because the society does not have small communities now. C．Because not many people say "hello" to each other when they meet. D．Because people no longer maintain close relations with each other.
A．A solution to man's food problem. B．A solution to the population problem. C．Advantages of soybean. D．How to develop good eating habits.