Correct Answer - D
All the naturally occurring monosaccharides belong to the D-Series because in the Fischer projection, the `OH` group at their respective penultimate carbon atom (or the last chiral carbon atom) is oriented towards right as in `D - (+) -` glyceraldehyde.
Synthetic sugars may have either `D -` or `L-` series. In `L-` series, the `OH` group on the penultimate carbon atom (or the last chiral carbon atom) is oriented toward left as in `L - (-) -` glyceraldehyde.