The correct option is B an aldehyde
Mild oxidation of a primary alcohol is done and it gives an aldehyde.
The reagents which can be used for this oxidation are pyridinium chlorochromate (PCC) and anhydrous CrO3. If we use anhydrous CrO3, the yield is poor, but if we use PCC, the yiels is better.
CH3−CH2−CH2−OHPCC/anhydrous CrO3−−−−−−−−−−−−−−→CH3−CH2−CHO