Gallstones are stone-like, solid concretions that found in the gallbladder, situated below the liver. The gallbladder stores bile salts, produced by the liver that helps to digest and dissolve cholesterol and other fats for rapid absorption. The most common type of gallstone is cholesterol stones, which account for approximately 80% of the total cases. The cholesterol gallstones are developed due to the precipitation of cholesterol in bile. This condition occurs when there is an increased amount of cholesterol that can be absorbed by bile salts in the gallbladder. So, the correct answer is option D.