The unbalanced chemical reactions given in List I show missing reagent or condition (?) which are provided in List II. Match List I with List Il and select the correct answer using the code given below the lists :

A

P-4, Q-2, R-3, S-1

B

P-3, Q-2, R-1, S-4

C

P-1, Q-4, R-2, S-3

D

P-3, Q-4, R-2, S-1