Pick up the incorrect statement from the following.
(a) Glucose exists in two different crystalline forms, α-D-glucose and β-D-glucose.
(b) Cyclic structure of α-D-glucose and β-D-glucose is called pyranose structure.
(c) α-D-glucose and β-D-glucose are enantiomers.
(d) Cellulose is a straight chain polysaccharide made up of only β-glucose units.