today is eptember 10th.It is --day.A:teacers B:teachers' C:t

选项B的(teachers')应该改为(Teachers')
B
因为这里需要一个形容词来修饰days,故A、D排除,且教师节翻译为”Teacher's Day“,故C排除,又因为教师节是专有名词,所以"Teacher's"的”T“要大写,所以选B.
即：
Today is eptember 10th.It is (teachers') day.