Match the equations with the type of reaction.
(> means arrow to the right)
1) 2Mg + O2 > 2MgO
2) 2H2O > 2H + O2
3) 2AgNO3 + Cu > Cu(NO3)2 + 2Ag
4) C3H8 + 5O 2 > 3CO2 + 4H2O

A) synthesis
B) Replacement
C) Combustion
D) Decomposition