题干
23. The writing brushes ____bamboo and animal’s hair.
A：are made of
B：is made from
C：is made of
D：are made u
答案(点此获取答案解析）
A
A：are made of
B：is made from
C：is made of
D：are made u
与
满足
，且
，则△ABC为 （ ）