题目

Leonardo da Vinci began painting the Mona Lisa in 1118. He was working 1 a special painting for a church at that time， 2 the church painting was not 3 well. An Italian businessman asked da Vinci to paint a picture of his second 4. This is the woman who 5 be seen in the Mona Lisa. All in all,the Mona Lisa is a very good example of da Vinci’s 6 and it satisfied the husband. Da Vinci used 7 and light in a clever 8 in the painting. Da Vinci loved science and 9 Right away a person can see that there is a lot of geometry(几何形状) in the Mona Lisa. The face of the Mona Lisa is made猪笼草是一种食虫植物，为了验证猪笼草分泌液中有蛋白酶，某学生设计了两组实验，如下图所示。在35℃水浴中保温一段时间后，甲、乙试管中加入适量的双缩脲试剂，丙、丁试管中不加任何试剂，下列实验能达到目的的是A．只有实验①能B．只有实验②能C．实验①、实验②都能D．实验①、实验②都不能