A:毛发
B:汗腺
C:趾甲
D:毛细血管
阅读如图所示的程序框图,运行相应的程序,输出的S的值等于( )
A. Let me see. I think it's a toilet for a pet(宠物).
B. Yes. I do. I like studying them.
C. Do you know anything about the public signs?
D. OK. What does that sign on the door mean?
据《元史·张雄飞传》所载,元世祖忽必烈问政于汉臣张雄飞。张雄飞答道:“古有御史台,为天子耳目,凡政事得失,民间疾苦,皆得言;百官奸邪,贪秽不职者,即纠劾之。为此,则纪纲举,天下治矣。”元世祖遂立御史台( )