Aldehydes are converted to primary alcohols when reacted with a reducing agent. Consider the two D-aldohexoses shown below: When both of them are reduced, one gives a chiral product and the other gives an achiral product. Explain.

• A. Starting with chiral molecules, the reduction product of D-talose becomes achiral since the conversion to alcohol removed the chiral center. This does not happen in the reduction of D-galactose which is why the product is still chiral.
• B. Starting with chiral molecules, the reduction product of D-galactose becomes achiral since the conversion to alcohol removed the chiral center. This does not happen in the reduction of D-talose which is why the product is still chiral.
• C. Starting with chiral molecules, the reduction product of D-talose becomes achiral due to a plane of symmetry. This is not present in the reduction product of D-galactose which is why the product is still chiral.
• D. Starting with chiral molecules, the reduction product of D-galactose becomes achiral due to a plane of symmetry. This is not present in the reduction product of D-talose which is why the product is still chiral.

Answer: (D)