Prime meridian is the answer
The answer is A. There is evidence from geologic rocks that there was an ice age 2.4 billion years ago and the glaciers had reached Western Australia and India. This ice age is associated with the cooling of the earth due to the Great Oxygenation event when the earth was filled with oxygen produced by photosynthetic organisms hence reducing the amount of greenhouse gases in the then atmosphere. There have been four other major ice ages after that.
The Mississippi, Missouri, Tennessee, and the Ohio River
Answer:
D
Explanation:
It's a perceptual region because it isn't labeled on a map or a functional region because it isn't defined by places nearby.