PLEASE HELP ILL GIVE YOU BRAINLIEST
The diagram below shows a portion of the concept map for the Rock Cycle:

Rock Cycle concept map showing an arrow pointing from sedimentary rock to volcanic rock and the step after volcanic rock is missing.

Which of these would best fit in the missing part of the cycle? (4 points)

a
Cooling

b
Heating

c
Sediments

d
Crystallization