(During the break) Amy: What are you looking at?  Ken: Some pictures of purple crow butterflies. Amy: Look at this one.     (45)    them are crossing the highway. Is it safe?  Ken: Of course not. Quite a few of them    (46)    by the traffic. Amy: Don’t people do anything to _(47)     them _(47)    the traffic flow? Ken: They sure do. See! This picture shows high nets_(48)   to protect them. Amy: By the way, my family are planning a trip to see beautiful butterflies in Yangmingshan. Are you interested in going with us?  Ken: Sure.      (49)  
【題組】45.
(A) One million
(B) Millions of
(C) Million
(D) Millions