题干
Leave the reference books behind, _____ you won't be able to think independently.
A：or
B：and
C：so
D：but
答案(点此获取答案解析）
A
Leave the reference books behind, _____ you won't be able to think independently.
A：or
B：and
C：so
D：but
和
的半径分别是5和4，
，则
正确的是