Among of the following statements, choose the correct statements about aldehydes,
A. Aldehydes have a carbonyl group (-C=O) at the end of the carbon chain.

B. The functional group of aldehydes is non-polar in nature.

C. The boiling point of aldehydes is higher than that of their corresponding alcohols.

D. Aldehydes can undergo oxidation to form carboxylic acids.

E. Formaldehyde is the simplest aldehyde.