The correct answer is - B. China has a large population, so its GDP per person is only modest.
China has the biggest population in the world, and big portion of that population is still earning small amount of money. Even though in the past few decades the GDP per capita has been improving, and in general, the Chinese people live much better than they used to, still considering the fact that very big portion of the population was very poor, it will take few more decades that the country's GDP per capita is ranked high.