An organic compound ‘A’ C8H6 on treatment with dilute H2SO4 containing mercuric sulphate gives compound ‘B’. This compound ‘B’ can also be obtained from a reaction of benzene with acetyl chloride in presence of anhy AlCl3. ‘B’ on treatment with I2 in aq. KOH gives ‘C’ and a yellow compound ‘D’. Identify A, B, C and D. Give the chemical reactions involved.
