Select the correct answer from the list.(1 point)
Astronomers think that most galaxies are centered by a_____which exerts_____that binds the galaxy together.
Astronomers think that most galaxies are centered by a supermassive black hole, which exerts gravity that binds the galaxy together.
Astronomers think that most galaxies are centered by a supermassive black hole, which exerts gravitational force that binds the galaxy together.
To find the correct answer, let's break down the question and eliminate the options one by one.
The question states that astronomers believe that most galaxies are centered by something that exerts a force binding the galaxy together.
Now let's analyze the options:
A) Black hole: A black hole is a massive object with such strong gravitational force that nothing, including light, can escape from it. Black holes are known to exist at the centers of many galaxies, and their gravitational force can indeed hold the galaxy together. This seems like a strong possibility.
B) Planet: While a planet can exert gravity, it is not large or massive enough to center an entire galaxy. Thus, we can eliminate this option.
C) Star: Like a planet, a single star is not large or massive enough to center an entire galaxy. Therefore, we can eliminate this option.
D) Asteroid: An asteroid is a relatively small object that orbits around a star but cannot center a galaxy. Hence, we can eliminate this option.
Based on the analysis, the correct answer would be A) Black hole. Astronomers believe that most galaxies are centered by a black hole that exerts a gravitational force strong enough to bind the galaxy together.