Answer: the Earth
Step-by-step explanation:
The astronomer Carl Sagan speaks of the Earth in the Pale Blue Dot. This is perhaps given away by the title which describes the dot as blue which is the same colour as Earth.
Carl Sagan speaks of how the Earth is home to humans who are diverse and believe in many different things such that we are a danger to ourselves. He mentions that it is the only planet that can harbor life at that point and so humans should treasure it and take care of it.