The Andes, Alps, and Rocky Mountains are some examples. It's usually where the snow line of mountains begins.
Answer:
NVA
Explanation:
https://www.answers.com/Q/Who_were_South_Vietnamese_who_supported_the_North_Vietnamese_during_the_Vietnam_War
Your answer would be A - The fertility rate is low.
I hope this is helpful. ✧
You are going to have to search it up online to get your answer