Which of the following substances will not give a yellow precipitate with $I_2/NaOH$?

The $Tishchenko$ reaction is used for the preparation of:

The major product $B$ formed in the following reaction sequence is
$p-Methoxybenzaldehyde$ $\xrightarrow[(ii) H_2O]{(i) C_2H_5MgBr} A$ $\xrightarrow{HCl} B$

The correct structure of product $A$ formed in the following reaction:
$PhCHO + PhCHO \xrightarrow[in\, D_2O]{NaOD} A + PhCOO^{-}$
($Ph$ is $-C_6H_5$)

Which of the following compounds reacts with $50\%$ sodium hydroxide solution to give the corresponding alcohol and acid?

In the given reaction,the number of chiral carbon$(s)$ in product $A$ is .......
(Where $Et$ is $-C_2H_5$)