Which of the following is not classified under energy releasing B-complex vitamin?
The B-complex vitamins may be sub-divided into energy-releasing (B1, B2, B6, biotin etc.)  and hematopoietic (folic acid and B12). Most of the water soluble vitamins exert the functions through their respective coenzymes while only one fat soluble vitamin (K) has been identified to function as a coenzyme.
Reference: Satyanarayana- Biochemistry, 3rd edition, pg-117
B1
B2
B6
B12