ninety-nine percent of the panda’s diet is bamboo, it also eats corn,
apples and sweet potatoes.
A. If
B. While
C. Because
D. Since
网友回答
A. If
(答案→)B. While
C. Because
D. Since
解析：考查连词。If如果，是否；While当什么时候，尽管；Because因为，由于；Since因为，自从。句意：尽管熊猫百分之九十九的食物是竹子，她也吃玉米，苹果和红薯。所以选B。