A.in mountains
A.in mountains
B.in stones
B.in stones
C.on animals
C.on animals
D.on a plain
D.on a plain
A.smaller
A.smaller
B.larger
B.larger
C.clearer
C.clearer
D.brighter
D.brighter
A.the participation of scientists
A.the participation of scientists
B.the emergence of the Internet
B.the emergence of the Internet
C.the birth of new theories
C.the birth of new theories
D.the interest in the Internet
D.the interest in the Internet
A.cautious
A.cautious
B.pessimistic
B.pessimistic
C.uncertain
C.uncertain
D.optimistic
D.optimistic