An organic compound '$\mathrm{A}$' $\left({\mathrm{C}}_9{\mathrm{H}}_{10}\mathrm{O}\right)$ when treated with conc. $\mathrm{HI}$ undergoes cleavage to yield compound '$\mathrm{B}$' and '$\mathrm{C}$'. '$\mathrm{B}$' gives yellow precipitate with ${\text{AgNO}}_3$ where as '$\mathrm{C}$' tautomerizes to '$\mathrm{D}$'. '$\mathrm{D}$' gives positive iodoform test. '$\mathrm{A}$' could be:

Benzene ring should not be attached to O atom otherwise it will yield phenol after reacting with$\mathrm{HI}$ so third option is prefect which gives benzyl iodide and it gives yellow precipitate of $\mathrm{AgI}$ after reacting with ${\mathrm{AgNO}}_3$. Another product tautomerises and gives acetaldehyde which gives iodoform test.