Answer:
(The first one)
The area around a star it is not too hot and not too cold for liquid water to exist
Explanation:
The habitable zone is the not-too-hot, not-too-cold region around a star where liquid water can exist on a planet's surface. Liquid water is a key ingredient for life as we know it, so exoplanets in their stars' habitable zones are compelling places to search for life.
