Compounds $$P$$ and $$R$$ upon ozonolysis produce $$Q$$ and $$S,$$ respectively. The molecular formula of $$Q$$ and $$S$$ is $${C_8}{H_8}O.Q$$ undergoes Canninzzaro reaction but not haloform reaction, whereas $$S$$ undergoes haloform reaction but not Cannizzaro reaction


The option(s) with suitable combination of $$P$$ and $$R,$$ respectively, is (are)

The major product of the following reaction is

Which of the following combination will produce $${H_2}$$ gas ?

The reaction of compound $$P$$ with $$C{H_3}MgBr$$ (excess) in $${\left( {{C_2}{H_5}} \right)_2}O$$ followed by addition of $${H_2}O$$ gives $$Q.$$ The compound $$Q$$ on treatment with $${H_2}S{O_4}$$ at $${0^ \circ }C$$ gives $$R.$$ The reaction of $$R$$ with $$C{H_3}COCl$$ in the presence of anhydrous $$AlC{l_3}$$ in $$C{H_2}C{l_2}$$ followed by treatment with $${H_2}O$$ producess compound $$S.$$ [$$Et$$ in compound $$P$$ is ethyl group]

The product $$S$$ is