问题
单项选择题
实验研究和调查研究的根本区别是()
A．是否进行随机抽样
B．是否进行随机化分组
C．是否主动对研究对象施加干预措施
D．以动物为研究对象，还是以人为研究对象
答案
参考答案：C
解析：是否对研究对象施加人为干预是实验研究和调查研究的根本区别。
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实验研究和调查研究的根本区别是()
A．是否进行随机抽样
B．是否进行随机化分组
C．是否主动对研究对象施加干预措施
D．以动物为研究对象，还是以人为研究对象
参考答案：C
解析：是否对研究对象施加人为干预是实验研究和调查研究的根本区别。
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| It was a cold winter's night when I stopped for gas on my way home from work. I was tired and had a slight 1 . I worked in a 2 doctor's office and this was one of those days when the unexpected happened, making the schedule run 3 than usual. It seemed I was going to be late 4 home and my husband, being the 5 person, would be ready to pronounce me late once again. Maybe 6 I hurried, I could still make it home. I was heading inside to 7 for my gas when I noticed an older couple at the counter. I heard them asking for 8 to the local hospital. It was the same hospital that I had just 9 a few minutes ago. The young man at the counter was trying to be 10 in explaining how to get there, with two other people making 11 . One of them was 12 trying to give them a whole different route back. It was then that I walked over to the couple and said, "Would you like to follow me to the 13 ?" A look of 14 crossed the woman's face. "I'm going right by there," I said, which wasn't a(an) 15 since I had just made up my mind to do 16 that. I got in my car and began the journey back. I was trying to watch to be sure they were right 17 me. It took only fifteen minutes to get there as rush hour traffic was beginning to 18 . I felt better than I had all day and my headache was nearly gone. Later, as I arrived home, my husband 19 , "So you aren't ever late any more." I said, "Sometimes it's 20 to be late." | |||
| ( )1. A. break ( )2. A. foreign ( )3. A. earlier ( )4. A. getting ( )5. A. tough ( )6. A. as ( )7. A. pay ( )8. A. opinions ( )9. A. reached ( )10. A. skilled ( )11. A. comments ( )12. A. only ( )13. A. station ( )14. A. panic ( )15. A. duty ( )16. A. partly ( )17. A. across ( )18. A. go up ( )19. A. teased ( )20. A. possible | B. fever B. common B. later B. cooking B. punctual B. since B. change B. trouble B. visited B. helpful B. promises B. still B. office B. relief B. fact B. properly B. before B. die down B. shouted B. special | C. cold C. busy C. easier C. calling C. generous C. while C. wait C. directions C. called C. experienced C. jokes C. even C. hospital C. sadness C. reason C. exactly C. beside C. speed up C. burst C. good | D. headache D. noisy D. simpler D. working D. careful D. if D. search D. money D. left D. active D. offers D. ever D. hotel D. peace D. lie D. perfectly D. behind D. turn down D. laughed D. safe |
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