As we all know，environmental pollution is still serious nowadays.Our group wanted to know how many students knew about each kind of the pollution and we wanted to learn how often they sorted（分类） rubbish.So we did a survey among the students in our school.Here are the results of our questionnaire（问卷）.

   The results of the questionnaire

Do you know about these problems？ How often do you sort rubbish？

（1）The survey is mainly about 　 　.

A．	scientific research
B．	environmental protection
C．	everyday habits
D．	physical education

（2）We can know there are 　 　parts in the questionnaire.

A．	two
B．	three
C．	four
D．	five

（3） 　 　is known by the fewest students.

A．	Air pollution
B．	Water pollution
C．	Noise pollution
D．	Global warming

（4） 　 　have begun to sort rubbish according to the chart（图表）.

A．	All of the students
B．	Most of the students
C．	Some of the students
D．	None of the students

（5）What can we learn from the results of the questionnaire？ 　 　

A．	Air pollution is noticed by a large number of students.
B．	The students don't realize the situation of the environment at all.
C．	Five kinds of environmental pollution are mentioned in the questionnaire.
D．	Most students take enough action to sort rubbish.