Only one of these statements about West Africa is true. Which is it?

• A Climate and agricultural belts as well as political regions in West Africa generally run east to west
• B Seasonal production of crops in the interior of West Africa is due more to the constraints of rainfall than to temperature
• C Nigeria alone has just half as much population as the rest of West Africa put together
• D The coastal regions of West Africa do not in any way stand in contrast to the inland regions
• E Inter-regional trade in West Africa is ompossible because the countries of West Africa have similar agricultural products