Christianity spread to as many, and actually more, countries than Islam, think for example of Latin America, which is predominantly Catholic!
Also, it it the world's biggest religion, and it has about 0.5 billion more followers than Islam. Therefore the false option is the last one: D.
A meander is a bend in a river
Contour lines show equal points of elevation
A North African trader traveling to West Africa in 1100 CE would most likely have spread Islam.