Which of the following statements about sustainable transportation system is TRUE?
A.It is safe.
B.It is capable.
C.It is friendly to the environment.
D.All of the above are right.
The author s attitude towards the sustainable transportation is______.
A.positive
B.critical
C.negative
D.doubtful
How should we understand the social benefits of a sustainable transportation system?
A.It should be efficient.
B.It should be safe.
C.It should be friendly.
D.It should be constructive.