Aurora Borealis (northern lights) occurs in

a. Troposphere

b. Mesosphere

c. Exosphere

d. Thermosphere

ANSWER: Thermosphere

Explanation:

- An aurora is a natural light display in the sky, predominantly seen in the high latitude (Arctic and Antarctic) regions.

- They are seen when electrically charged particles from the sun enters the earth's atmosphere.

- In the north, they are called as aurora borealis while in the south they are called aurora australis.