Covalent bond can undergo fission in two different ways. The correct representation involving a heterolytic fission of ${\mathrm{CH}}_3—\mathrm{Br}$ is

In which of the following representations given below spatial arrangement of group/ atom different from that given in structure $\mathrm{A}$?

Which of the following pairs are not functional group isomers?

Note: Consider structures I to VII and answer the question

 Which of the above compounds form pairs of metamers?
 

Note: Consider structures I to VII and answer the question

Identify the pairs of compounds which are functional group isomers.