Question

Read this excerpt from "Why Are They Called Black Holes?"

When the star gets big enough and hot enough, the central core has enough energy to fuse hydrogen atoms into helium atoms. These reactions release energy that pushes matter out, fighting the force of gravity and keeping the star from collapsing into itself. After many millions or billions of years, the star runs out of hydrogen and energy. Then the star "dies" and collapses into a dense little ball with tons of gravity. Albert Einstein's theory of relativity predicted that black holes would have to exist if a dead star had enough gravity.
How long can a star live?
billions of years
just until it gets hot
fewer than one million years
until it is big enough to become a black hole

Answer 1

A

Step-by-step explanation:

Answer 2

A star can live for billions of years: Option A.

Step-by-step explanation:

The given excerpt clearly indicates that a star can run out of hydrogen and energy only after millions or billions of years. Only then it collapses to a little ball with gravity. This means it would live till those millions or billions of years.

'Black hole' is a region in the space which has such strong gravitational force that it pulls every object that passes through it. Albert Einstein predicted that black star would exist if a dead star also had enough gravity. Hence, "option A" is the correct one.