1. How is the earth a unique planet in the solar system?

Earth is called as a unique planet because it is the only planet known that supports life. It has the moderate climatic conditions favouring life. It is also beautiful with so many types of flora and fauna and so many types of species.It has all types of geographical features and the living beings adapt themselves according to the climatic conditions.

or we can say,

Earth is called unique because environment of earth does not match with any other planet's environment!Any form of life can survive on earth but not at any other planetEarth's avg temperature is also not very much high or low so its unique in solar system.