Mr. Mike, in ______ supermarket we bought an ipad last week, will give us a report on management this evening.

A．who

B．which

C．whose

D．whom

推进“四改”和“三治”工作是村容村貌整治，完善村庄建设规划的内容之一。请问这里的“四改”具体指的是什么？