Compound P on treatement with `CH_(2)N_(2)` (diazomethane) produces compound Q. compound Q on reaction with Hl produces two alkyl iodides R and S . Alkyl iodide S with higher number of carbon atoms on reaction with KCN followed by hydrolysis gives 3-methylbutanoic acid. the compound P is
A. 2-butanol
B. 1-butanol
C. 2-methyl-2-propanol
D. 2-methyl-1-propanol
