The conversion shown in the image can be achieved by:

Methyl ketone group is identified by

The reaction sequence is as follows:
$Cyclopentanecarboxamide$ $\xrightarrow{P_2O_5, \Delta} W$ $\xrightarrow{CH_3MgBr, H_3^+O} X$ $\xrightarrow{Ca(OH)_2, I_2 (\text{yellow ppt.})} Y$ $\xrightarrow{\Delta} Z$
$Z$ is:

What reagent and/or reaction conditions would you choose to bring about the conversion shown in the image?

Compound $(A)$ with molecular formula $C_6H_{12}O_3$ gives a positive iodoform test and a negative Tollens' test. Upon treatment with water and a drop of $H_2SO_4$,it gives a positive Tollens' test. Compound $(A)$ is:

Compound $(A)$,$C_6H_{12}O_3$,when treated with $I_2$ in aqueous sodium hydroxide gives a yellow precipitate. When $(A)$ is treated with Tollens' reagent,no reaction occurs. When $(A)$ is hydrolysed and then treated with Tollens' reagent,a silver mirror is formed in the test tube. Compound $(A)$ will be