Aldehyde cyanohydrins are chiral and are formed as two enantiomers. Rotate the structures to confirm they are non-superimposable.
A bond must be broken to change from one configuration to another.
Using the Jmol structures above manipulate the structures until you are satisfied that a bond would have to be broken and remade to change between the two structures.
Going from one enantiomer to the other configuration requires a bond to be broken.