How Does a Black Hole Form from a Massive Star

Multiple Choice

How does a black hole form from a massive star?

A) During a supernova,if a star is massive enough for its gravity to overcome neutron degeneracy of the core,the core will be compressed until it becomes a black hole.
B) Any star that is more massive than 8 solar masses will undergo a supernova explosion and leave behind a black-hole remnant.
C) If enough mass is accreted by a white-dwarf star so that it exceeds the 1.4-solar-mass limit,it will undergo a supernova explosion and leave behind a black-hole remnant.
D) If enough mass is accreted by a neutron star,it will undergo a supernova explosion and leave behind a black-hole remnant.
E) A black hole forms when two massive main-sequence stars collide.