下列属于自卑表现的有（  ）

48－a=10                   48－b=9

48－c=8                   48－d=7

    Jiaozi is the Chinese name of dumplings. We have all kinds of dumplings with meat or vegetables in it. Jiaozi is very delicious and it is very popular (受人喜爱的) in China, especially (尤其) during Spring Festival. People usually eat jiaozi on the eve of Spring Festival. Why do people like eating jiaozi? Because Spring Festival is Chinese New Year. People eat round jiaozi to show their wishes for good luck. The history of jiaozi is about 2, 000 years. Eating jiaozi is a very happy thing. When all the families make jiaozi together, you'll feel very happy.

在泸州市2016年初中生物实验操作考试中，小张同学观察人血的永久涂片时，显微镜处于光线较暗的环境中，下列操作组合中正确的是（　　）