All of those systems are vital for a person to survive. If an organ stopped functioning it could cause you to die unless it is your liver and a few others.
After millions of years, the remains of living things will turn into fossil fuels which are natural fuels. The combustion of these fossil fuels is important for the running of machinery, raising temperature in reactions and many more.
C( both options. Hope it helps!!!!
The process responsible for this is mass movement.
