Final answer:
The enantiomer of alpha-D-fructose is beta-D-fructose. Enantiomers are mirror images of each other with the same chemical structure.
Step-by-step explanation:
The enantiomer of alpha-D-fructose is beta-D-fructose. Enantiomers are molecules that are mirror images of each other and have the same chemical structure and bonds, but differ in their three-dimensional placement of atoms. In the case of fructose, the alpha and beta forms are enantiomers of each other. The alpha form has the -OH group on the anomeric carbon atom pointing to the right, while the beta form has the -OH group pointing to the left.