Complete the sentences with the given words in their proper forms.

1. The nursery is bright and _________ with plenty of toys. ( cheerfully)

2. The retired people usually take up a hobby such as raising flowers or birds to relieve the _________ of

     retirement. (boring)

3. They have to have a basic ___________ of computer in order to use the advanced technology. (understand)

4. The specialist watched the _________ of the snake for a long time. (move)

5. The last decade has a witnessed (见证) a serious rise in the levels of racism (种族歧视) and __________ to

     Black and ethnic groups. (种族群体) (hostile)

测验所得分数（测值）一致性的测验性能质量指标称为（）

A.难度

B.区分度

C.信度

D.效度