What happened to the flowers which were put in a laboratory in constant darkness？
A. They didn't open at all.
B. They opened as if they were in a normal garden.
C. They have circadian cycles of activity.
D. They died without knowing the time of day.
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Which of the following is true according to the talk？
A. There has been a slower population growth in the past ten years.
B. The world's rate is higher than ten years ago.
C. Families are as large as before.
D. Birth control has been carried out well all over the world.
If you like children and you could offer a happy family to a homeless child, you may go to
A. Street Food
B. Night Shelter
Children't Home
D. Children's Hospice
Why did people make gardens into "flower clock"？
A. To make gardens into a round shape.
B. To look at the flower in the gardens at different times of the year.
C. To attract people.
D. To know the time.
The relationship between technology and development is complicated. At times the negative
A. withdraw
B. discharge
C. maximize
D. outweigh
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