题目内容：
根据材料，回答问题。E
In fall 2006．the National Basketball Association(NBA)started using basketballs made withsvnthetic，or man-made，material instead of leather．They made the change because they wanted evcry basketball they use to feel and bounce the same．Not all leather balls are exactly alike in weightor how they bounce，but the synthetic bails are．
However，some players complained fight away that the new balls bounced differently and were actually harder to control than the leather ones.
Physics helped answer questions about why the new baUs felt different .For example,the scien-tists studied fliction，which in this case affects the ability of a player to hold onto a ball, “The greater the friction.the better it will stick to his hand，”explains a scientist.
Tests on both wet and dry balls showed that while the synthetic ball was easier to hold onto when dry，it had less friction and became much harder to hold onto when wet．That's because sweat stays on the surface of the synthetic balls but gets taken into the leather balls．
The scientists also tested bounce and found that the logo printed on the new balls made their surface uneven and caused them to bounce a little strangely compared with the leather balls．
In January，the NBA went back to using the leather bails They aren’t perfect，but for now,that’s just the way the ball bounces．
Why were the synthetic balls expected to be used in NBA according to the text? A．Because they are easier to control．
B．Because they waste less material．
C．Because they look exactly alike．
D．Because they feel and bounce alike．
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