A, B, and C are three aldohexoses. Compounds A and B yield the same optically active alditol when they are reduced with hydrogen and a caralyst; A and B yield different phenylosazones when treated with phenylhydrazine; B and C give the same phenylosazone but different alditols. Assuming that all are $\mathrm{D}$ sugars, give names and structures for $\mathbf{A}, \mathbf{B},$ and $\mathbf{C}$.0