CH4 + 2 CO2 —> 2 H2O What type of chemical reaction is taking place in this chemical equation?

Synthesis
Decomposition
Single Replacement
Double Replacement
Combustion

I think it’s combustion

That result from subduction of oceanic plates beneath lighter continental plates. most of the earth's volcanoes are located around the pacific ring of fire because that the location of most of the earth's subduction zones.

It’s the energy source of stars