Which of the following statements about vitamin B₁₂ is incorrect ? 

Vitamin B₁₂​ does not exist in plants, but is synthesized by microorganisms (bacteria, fungi). 

Therefore, humans must obtain B₁₂​ in the diet, either from animal sources (red meat, fish, poultry, eggs and dairy products).

Cobalt is also an essential trace element for humans, and is found at the center of vitamin B₁₂ and a range of other co-enzymes called cobalamins.