I would guess A. If you think of greenhouse gasses in the atmosphere they trap heat in. that is what causes global warming.
Answer:
B. Location
Explanation:
A realm is the largest unit in which the inhabited world can be divided. Realms can be spacially defined by area, distances, directions, location, proximity, clustering, accessibility, isolation, etc.
UMSL
D. Temperate regions receive more solar energy and heat per unit area then tropical regions.
Condensation. thats when the water vapor cools down to form clouds