Hydrogenation of fatty acid is ?

Ans. is 'c' i.e., Addition of hydrogen to unsaturated fatty acidAddition of hydrogen atoms to unsaturated fatty acid refers to hydrogenation. It reduces the number of double bonds in the unsaturated fats.Hydrogenation of unsaturated fats in the presence of a catalyst (nickle) in known as "hardening", because it conves liquid vegetable oils into solid fats e.g. margarines, vegetable ghee, etc.