加苏丹Ⅲ试液呈橘红色至红色的为
A．木质化细胞壁B．木栓化或角质化细胞壁C．纤维素细胞壁D．硅质化细胞壁E．以上均不是
参考答案：B
I’ll never understand how it __________ that you were late three times a week.
A．came up with
B．came across
C．came about
D．came out
ATC“指令”就是（）.
