题目

经检测，刚挤出的鲜牛奶中有两种物质，它们的分子式分别为：C12H22O11和C1864H3012N168O221。这两种物质分别是 A．脂肪和核酸            B．乳糖和蛋白质         C．乳糖和核酸            D．蔗糖和蛋白质 答案：B(   ) 5. These flowers are so         . Those flowers are        than these ones.   A. beautiful;beautiful   B. more beautiful;more beautiful   C. the most beautiful;more beautiful   D. beautiful;more beautiful