Predict the stereochemistry of the product when a $d$ and $l$-amine mixture reacts with an $l$-acid.

Write the chemical reactions for the following conversions:
$1.$ Aniline to Picric acid
$2.$ Ethanal to Butan$-2-$ol

An organic compound $A$ on reduction gives compound $B$,which on reaction with trichloromethane and caustic potash forms $C$. The compound $C$ on catalytic reduction gives $N$-methylbenzenamine. The compound $A$ is,

$(A)$ $\xrightarrow{KOBr} (B)$ $\xrightarrow[KOH]{CHCl_3} (C)$ $\xrightarrow{LiAlH_4} \text{Structure of } (C) \text{ is}$

Consider the following reaction sequence:
$p$-Nitrotoluene $\xrightarrow{P} Q$ $\xrightarrow{R} S$ $\xrightarrow{H_2O} T$
$S \xrightarrow{U} \text{Benzoic acid}$
Identify the correct statements from the following:
$(A) P = H_2/Pd, \text{ethanol}; R = NaNO_2/HCl; U = 1. H_3PO_2, 2. KMnO_4-KOH, \text{heat}$
$(B) P = Sn/HCl; R = HNO_2; S = p-\text{toluenediazonium chloride}$
$(C) S = p-\text{toluenediazonium chloride}; T = p-\text{cresol}; U = 1. CH_3CH_2OH, 2. KMnO_4-KOH, \text{heat}$
$(D) Q = p-\text{nitrobenzoic acid}; R = H_2/Pd, \text{ethanol}; T = p-\text{cresol}$
Which of the following combinations is correct?

The product $(B)$ is: