题目如图,△ABC\triangle ABC△ABC中,AB=7AB=7AB=7,AC=8AC=8AC=8,BDBDBD、CDCDCD分别平分∠ABC\angle ABC∠ABC、∠ACB\angle ACB∠ACB,过点DDD作直线平行于BCBCBC,交ABABAB、ACACAC于EEE、FFF,则△AEF\triangle AEF△AEF的周长为( )A.999B.111111C.151515D.181818知识点:平行线的性质章节:图形的性质 / 相交线与平行线