Less nutritious food, dramatic change in temperatures around the world, the rising of sea levels and extreme weather events
The two tectonic plates meet at point one. One is moving under the other, shown by the two arrows on the top pointing towards each other. The denser plate (left side) is subducted. This means the denser plate begins to go under the less dense plate. The lithosphere (crust/tectonic plate) is mainly solid rock. As it begins to go into the mantle it will begin to heat up as the mantle is hotter than the surface. The solid surface becomes a molten rock, known as magma. It melts as it goes down.
That would be B. Latin America
Mountain chains and river systems generally run North-South throughout the continent thus making for formidable barriers to East-West expansion.
Both are igneous rocks, but whereas volcanic rocks are formed from cooling lava on the surface, plutonic rocks are formed from cooling magma below the surface. So plutonic rock is an igneous intrusive rock, while volcanic rock is extrusive.