An organic compound A (C₅H₈​) on hydrogenation gives compound B (C₅​H₁₂​). Compound A on ozonolysis gives methanal and 2-ketopropanal. The compound A is:
a) Isoprene
b) 2-Methyl-1-butene
c) 1-Pentene
d) 2-Methyl-2-butene