Match List I (Fuel Gases) with List II (Major Constituents) and select the correct answer using the codes given below.
List I
(A) CNG
(B) Coal gas
(C) LPG
(D) Water gas

List II
1. Carbon monoxide, Hydrogen
2. Butane, Propane
3. Methane, Ethane
4. Hydrogen, Methane, Carbon monoxide