If extreme heat and pressure change rock into gneiss, then what changes rock into gneiss?

Answer choices:
- weak heat and low pressure
 - The bending of a ray of light
 - extreme cold and pressure
 - heat is produced
 - movement of tectonic plates
 - tectonic plates being pushed together
 - extreme heat and pressure
 - extreme heat and no pressure

 

       extreme heat and pressure   