How do low mass stars become white dwarfs?

Explanation:

Because the core is out of fuel, the white dwarf will eventually cool to a black dwarf. ... This will take many billions of years to cool. Degenerate gas pressure inside the core continues to support the star so it doesn't collapse.

because the core is out of fuel, the white dwarf will eventually cool to a black dwarf this will take many billions of year to cool . degenerate gas pressure inside the core continuous to support the star so it doesn't collapse

law of conservation of matter

i think the answer is terrae but not 100 percent sure. ▓▬▬ §