The carbonyl compound that does not undergo aldol condensation is

Which of the following compounds will give a silver mirror test with ammoniacal silver nitrate (Tollens' reagent)?
$(A)$ Formic acid
$(B)$ Formaldehyde
$(C)$ Benzaldehyde
$(D)$ Acetone
Choose the correct answer from the options given below:

The major products of the following reaction are:

In the given reaction sequence,identify the structure of $(B)$:
Cyclohexanol $\xrightarrow{PCC}$ $(A)$ $\xrightarrow{H-CHO, \text{dil. } KOH, \Delta}$ $(B)$

Which of the following compounds does not give an Aldol condensation reaction?

The product $(A)$ is: