The active ion in Tollen's reagent is

Identify the correct statements about $Z$ in the following reaction sequence:
$C_2H_5NH_2$ $\xrightarrow[NaNO_2 / HCl]{} X$ $\xrightarrow{H_2O} Y$ $\xrightarrow{Cu / 573 \ K} Z$
$I$. $Z$ is an aldehyde
$II$. $Z$ undergoes Cannizzaro reaction
$III$. $Z$ gives iodoform test
$IV$. $Z$ does not give test with Tollens' reagent

The products $A$ and $B$ of the below reaction sequence are

Which of the following reactions will not result in the formation of carbon-carbon bonds?

$p$-cresol reacts with chloroform in an alkaline medium to give compound $A$,which adds hydrogen cyanide to form compound $B$. The latter,on acidic hydrolysis,gives a chiral carboxylic acid. The structure of the carboxylic acid is:

Select the best reagent to carry out the above conversion.