Compound A was prepared by the oxidation of compound B

Compound A was prepared by the oxidation of compound B with alkaline $KMnO_{4}$ Compound A on reduction with lithium aluminium hydride gets converted back to compound B. When compound A is heated with compound B in the presence of $H_{2}SO_{4}$, it produces fruity smell of compound C. To which family, the compounds A, B and C belongs to?