The product $(Z)$ is:

Styrene on reaction with reagent $X$ gave $Y$, which on hydrolysis followed by oxidation gave $Z$. $Z$ gives a positive $2,4-DNP$ test but does not give the iodoform test. What are $X$ and $Z$ respectively?

The dibromo compound $[P]$ (molecular formula : $C_{9}H_{10}Br_{2}$) when heated with excess sodamide followed by treatment with dilute $HCl$ gives $[Q]$. On warming $[Q]$ with mercuric sulphate and dilute sulphuric acid yields $[R]$ which gives positive Iodoform test but negative Tollen's test. The compound $[P]$ is:

Compound $A$ $(C_{11}H_{14}O_4)$ is a degradation product of the antibiotic vermiculine. It undergoes the following reactions as shown in the image. Identify the unknown compound $C$ $(C_{11}H_{18}O_2)$.

$A$ hydrocarbon with molecular formula $C_4H_6$ undergoes the following reactions:
$A$. Decolourises molecular bromine.
$B$. Reacts with $HBr$.
$C$. Addition of ozone and then cleavage of the ozonide by $Zn / H_2O$ gives the product $C_4H_6O_2$.
Then,the structure of the hydrocarbon is:

Identify the reaction that does not produce an alkene.