An organic compound 'A' (molecular formula ${\mathrm{C}}_6{\mathrm{H}}_{10}\mathrm{O}$) forms hydrazone and reduces Tollens' reagent. When treated with ${\mathrm{CH}}_3\mathrm{MgBr}$ followed by hydrolysis 'A' gives a chiral compound 'B'. Compound $\text{'}\mathrm{B}\text{'}$ on oxidation with potassium dichromate/acid gives compound 'C'. Compound 'C' undergoes haloform reaction and gives cyclopentane carboxylic acid as oxidation product. Identify A,B,C and write the sequence of the reactions.