Which of the following compounds undergo Aldol condensation followed by dehydration to give 3-phenylprop-2-en-1-al?

$$\text { Identify }[\mathrm{B}] \text { and }[\mathrm{C}] \text { formed in the reactions given below. }$$

Which one of the following statements is incorrect regarding acetal and ketal formation when Propanal and Propanone are separately reacted with Ethanol in presence of anhydrous $$\mathrm{HCl}$$ gas.

A Carbonyl compound $$\mathrm{X}$$ when reacted with Methyl magnesium bromide followed by hydrolysis gave product $$\mathrm{Y}$$. When $$\mathrm{Y}$$ is heated with $$\mathrm{Cu}$$ at $$573 \mathrm{~K}$$, it gave $$\mathrm{Z}$$ (2- Methylbut-2-ene) as one of the products. Identify $$\mathrm{X}$$.