Match List I with List II.
              List I                                                         List II.
A. Propanamine and N-Methylethanamine          I. Metamers
B. Hexan-2-one and Hexan-3-one                        II. Positional isomers
C. Ethanamide and Hydroxyethanimine             III. Functional isomers
D. o-nitrophenol and pnitrophenol                     IV. Tautomers
Choose the correct answer from the options given below :-