单项选择题
A．two hundred and fifty million B．one hundred million C．about half of the total population in the world D．seven thousand million
A．the world plan to help the illiterates learn to read and write will be realized very soon B．UNESCO is the most powerful organization to solve the problem of illiteracy C．responsible citizens should have been trained D．in Africa over 80% of people can not read and write
A．3.4% of the total population in the world B．2.5 % of the total illiterate in the world C．1.7% of the total population in the word D．1.7 % of the total illiterate in the world