问题: Inparagraph2,theauthormentionsastudyofseriousabdominalinjuries______.
A: todiscusshowabdominalinjuriesinchildrenoccur
B:toshowthatmorethanathirdinjurieswerecausedbybicycleaccidents
C:topointoutwhatthecountermeasurescanbe
D:totelluswhyKristyArbogastbegantheproject
