Fact 1: If a planet becomes too hot then that planet cannot sustain life.

Fact 2: If a planet is too close to a star, then it will be too hot for liquid water to exist.

Given the two facts above, answer the question "If a planet cannot sustain life, then the planet may be too close to what?" with the following options: 
- a ship
 - Sun
 - sunlight
 - earth
 - a crater
 - an object
 - a moon
 - a star


 

        a star 