Arrange these compounds in decreasing order of reactivity for the nucleophilic addition reaction :
$I.$ Acid chloride $II.$ Aldehyde
$III.$ Ketone $IV.$ Ester
Select the correct answer from the codes given below :

The structure of $(B)$ is

The most appropriate reagent to distinguish between acetaldehyde and formaldehyde is

Choose the incorrect statement among the following.
$A$. The reactivity of aromatic aldehydes and ketones is less than that of aliphatic carbonyl compounds towards nucleophilic addition reactions.
$B$. Benzaldehyde does not give Fehling's test.
$C$. The $\alpha$-$H$ atoms in ethanal are acidic in nature.
$D$. $p$-nitro benzaldehyde is less reactive than benzaldehyde towards nucleophilic addition reactions.

Which reaction is correctly matched with its name?

The reaction of $A$ to give $B$ and $C$ as shown in the reaction scheme is an example of:
$CH_2=CH_2$ $\xrightarrow[2. Zn/H_2O]{1. O_3} A$ $\xrightarrow{Conc. NaOH} B + C$
(Where $B$ is an alcohol and $C$ is a sodium salt of a carboxylic acid)