题目

—The lecture about 3D technology was very interesting.—It's a pity. How I wish I ________ time to attend it. A . had B . have C . had had D . have had 答案：C下列结构中，与小肠的吸收功能无关的是（ ）A. 小肠内表面有皱襞和小肠绒毛B. 小肠绒毛内有毛细血管和毛细淋巴管C. 小肠绒毛壁薄D. 小肠内有肠腺