Which atmospheric gases are thought to cause global warming?

Witch one is it soo it the the question b.a,b,c,d

Scientists think that convection currents flow in earth’s a. continents. b. mantle. c. lithosphere. d. inner core.

What two advantages do the coastal countries of west africa have over the sahel countriesfertile soil and mineral resources temperatures and terrain human resources and natural resources weather patterns and location