Which of the following reagents can distinguish between propanal and propanone?

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:

An aromatic compound $A$ (Molecular formula $C_{8}H_{8}O$) gives a positive $2,4-DNP$ test. It gives a yellow precipitate of compound $B$ on treatment with iodine and sodium hydroxide solution. Compound $A$ does not give Tollen's or Fehling's test. On drastic oxidation with potassium permanganate,it forms a carboxylic acid $C$ (Molecular formula $C_{7}H_{6}O_{2}$),which is also formed along with the yellow compound in the above reaction. Identify $A, B$ and $C$ and write all the reactions involved.

Acetal is obtained by reacting which of the following in the presence of dry $HCl$ and alcohol?

Which of the following reducing reagents will be suitable for the conversion shown below?
(Structure: $3-$methylcyclohexanone to methylcyclohexane)

The appropriate reagent for the following transformation is