A convergent plate boundary is when two plates move towards each other, also known as a destructive plate boundary. So, the answer is A.
The more people that are migrating to urban areas (urbanization) needs more crops for the citizens which causes more people to grow crops and without crop rotating or methods to prevent soil degradation. More likely answer is that more industry grows in the urbanized areas and they have poor management of the soil which causes soil degradation<span />
Nuclear fusion reactions combine hydrogen to helium
