A. hot is the correct answer.
Hope it helps!
<span>the heated filament will react with the oxygen in the air but now with the argon, which is a noble gas and hardly ever reacts.</span>
Answer: Black hole.
Explanation:
As the massive star "compacts" under its own gravity, it triggers a massive supernova, after this point the remains of the star can become a neutron star, which is a very compact star made primarily, as the name says, of neutrons. The other possibility is a black hole, which is a finite region of space wherein it's interior there is a big concentration of mass, which creates a gravitational field strong enough that there is no particle that can escape it.