Reductive ozonolysis of benzene gives:

The major product obtained in the given reaction is:

Among the following, the reaction that proceeds through an electrophilic substitution, is:

In the reaction scheme shown below, $\mathrm{Q}, \mathrm{R},$ and $\mathrm{S}$ are the major products.

 The correct structure of 

The major product of the following reaction is:

 The major product of the following reaction is:

In the reaction $\left(\mathrm{X}\right)$ and $\left(\mathrm{Y}\right)$ are respectively.

What are the starting materials for the preparation of the following?