What element marks the heaviest product of sustained core fusion within a supergiant before collapse?

Answer

Iron ($^{56} ext{Fe}$)

The systematic chain reaction of fusion within the star's core proceeds up the periodic table until silicon fuses into iron, which is the final stable product of this standard thermonuclear process.

What element marks the heaviest product of sustained core fusion within a supergiant before collapse?
Elementstarsynthesissuper giant