About 71 percent of the earth’s surface is covered by water. Earth has water in all its forms i.e. Liquid, ice and vapour. Earth is the only known planet to have consistent stable bodies of liquid on its surface. Earth appears blue in our solar system.

What is the main idea of the story?

A. Earth has unique features.
B. Earth is the blue planet
C. Earth is round in shape
D. Moon is very close to the sun

Answer: B

Solution:
The main idea of the story is that Earth is called blue planet in our solar system due to its abundance of water in all its forms (liquid, ice, and vapour) and its consistent stable bodies of liquid on its surface. This characteristic sets Earth apart from other known planets and is symbolised by its blue appearance in our solar system.