This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Surgery
[{'content': 'Cholesterol Stone made up of \nSelect and explain. \nA. Amorphous Cholesterol Monohydrate, B. Crystalline Cholesterol Monohydrate, C. Cholesterol Polyhydrate, D. Cholesterol with Calcium Palmitate', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Composition of Each Stones: - Cholesterol Stones: - * Cholesterol Stones are formed by Nucleation of Cholesterol Monohydrate crystals from multilamellar vesicles. * MC type of Gall stone in Western Countries Pigment Stones: - * Contains < 30% Cholesterol * Brown Pigment Stone- Composed of Calcium Bilirubinate, Calcium Palmitate and Calcium Stearate as well as Cholesterol. * Black Pigment Stone- Composed of Largely Insoluble Bilirubin pigment Polymer mixed with Calcium Phosphate and Calcium Bicarbonate. Ref:- Bailey and Love 27th Edition; Pg num:- 1198', 'role': 'assistant'}]