Question

Which vitamin is critical to allow the transformation of folate into an active form?

Answer 1

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Explanation:

Folic acid is the synthetic form of vitamin B9.

This acid must remove homocysteine, so it's firstly converted to its active form: L-methylfolate (5-MTHF).

"All the biological functions of folic acid are performed by tetrahydrofolate and other derivatives". - according to Wikipedia.