Aby-product of hydrogenation is select one: a. trans fatty acids. b. triglycerides. c. cholesterol. d. monounsaturated fats.

d. monounsaturated fats.

Explanation:

Hydrogenation reaction is a type of reaction in which unsaturated fatty acids are converted into either saturated fatty acids  or monounsaturated fats in the presence of dihydrogen (H₂) and a catalyst like nickel. Due to the addition of hydrogen in the unsaturated fatty acid it gets reduced and only a fewer bonds now exist between the carbons which make the backbone of fatty acids. Unsaturated fatty acids exist in liquid form while saturated fatty acids exist in semi-sold or solid form at room temperature.

Hydrogenation is an important process which is meant for increasing the shelf life of vegetable oils. Unsaturated fatty acids which are present in refined oil get spoiled easily but saturated fatty acids or monounsaturated fats which are present in hydrogenated oils last for a longer time.

i believe it would be the lungs.

i have to report this, it doesn't relate to biology