From the following transformations,A. Epoxidation of alkeneB. Dioldehydrase reactionC. Conversion of ribonucleotide-to-deoxyribonucleotideD. 1, 2-carbon shift in organic substrates those promoted by coenzyme $\mathrm{B}_{12}$ are
(a)A and B
(b)B, C and D
(c)A, B and D
(d)A, B and C
Answer
Answer: B ✓ checked by 4AB · confidence high
Explanation
Coenzyme B₁₂ (adenosylcobalamin) drives radical 1,2-rearrangements: diol dehydrase, ribonucleotide reductase (class II) and carbon-skeleton mutases; alkene epoxidation is not a B₁₂ reaction. B, C and D.