A:if
B:unle
C:though
D:while
Miss Read is good ____________ music. She is good ____________ children in the music club.
小华视物时成像情况如图所示,医生向她介绍激光手术:通过激光烧蚀厚度均匀的透明眼角膜,使之改变形状,实现视力矫正.手术后的眼角膜形状应为下列图中的( )