Fact-check each of the claims in the following answer.

Question: Black Holes

Answer: Black holes are theoretical objects that have an intense gravitational field that can not be escaped from. They are believed to appear as the result of the death of a massive star, or supernova. The collapse of material into a black hole results in such powerful gravitational forces that nothing - not even light - can ever escape again.
"Black holes are theoretical objects that have an intense gravitational field that can not be escaped from." - Correct [2].
"They are believed to appear as the result of the death of a massive star, or supernova." - Correct [1].
"The collapse of material into a black hole results in such powerful gravitational forces that nothing - not even light - can ever escape again." - Mostly correct [3]. No light can escape from the black hole, but the black hole itself is not visible.
"Black holes are theoretical objects that have an intense gravitational field that can not be escaped from." - Correct [1, 3].
"They are believed to appear as the result of the death of a massive star, or supernova." - Correct [1].
"The collapse of material into a black hole results in such powerful gravitational forces that nothing - not even light - can ever escape again." - Mostly correct. Black holes do have an intense gravitational field that cannot be escaped, but matter and energy can escape as long as they don't fall inside the event horizon. [1, 2].