Is vitamin D organic or inorganic?

Answer 1

It's arbitrary (and some chemicals are classed as both);
but in general organic contains carbon molecules and/or those related to life. It is the chemistry of carbon containing compounds.
Inorganic is everything else and generally do not contain carbon (with some exceptions).

Answer 2

No. Vitamins are organic molecules. They are simply molecules used by organisms to aid in certain chemical reactions. They are not broken down in these reactions or used for energy.

Answer 3

but it is fat soluble and lipids (fats) are organic.

so organic

Answer 4

organic