A:that; which
B:that; that
C:what; what
D:what; which
____ ____ ____ T-shirt____my mom's.
周鸣同学手拿一段钢锯条,将钢锯条的一端靠近小磁针的N极,他发现小磁针向钢锯条靠近,根据观察到的现象,他做出了以下几种判断,你认为正确的是( )