Identify the relationship of the given structure with each of the following structures as enantiomers, diastereomers, or identical compounds.

• A. (a) Identical compounds
  (b) Enantiomers
  (c) Diastereomers
  (d) Identical compounds
• B. (a) Enantiomers
  (b) Identical compounds
  (c) Enantiomers
  (d) Diastereomers
• C. (a) Enantiomers
  (b) Constitutional isomers
  (c) Enantiomers
  (d) Enantiomers
• D. (a) Constitutional isomers
  (b) Enantiomers
  (c) Diastereomers
  (d) Enantiomers

Answer: (A)