Which of the following choices must occur during all chemical changes

It would be C! An energy change. Usually it changes heat - could be less or more.
I hope all is well, and you pass! Good luck, rockstar! You got this. (:

Non metal is an element or substance that is not a metal metal is a solid material that is typically hard, shiny, malleable, fusible, and ductile, with good electrical and thermal conductivitymetalloid is an element (e.g., germanium or silicon) whose properties are intermediate between those of metals and solid nonmetals. they are electrical semiconductors.

The metal is named first