Final answer:
Disaccharides form a glycosidic linkage between the anomeric carbon of one monosaccharide and the hydroxyl group of another, through a dehydration reaction.
Step-by-step explanation:
Disaccharides form a glycosidic linkage through a dehydration reaction, where two monosaccharides combine, and water is released to form a covalent bond. Specifically, this bond is formed between the anomeric carbon (often the carbon 1 of the monosaccharide involved in the ring closure) of one monosaccharide and the hydroxyl group of the other monosaccharide. The correct answer to your question is that the glycosidic linkage in disaccharides is formed between the carbonyl carbon of one monosaccharide (which becomes the anomeric carbon in the cyclic form) and the hydroxyl group of another monosaccharide.