You need to identify whether the page is in Edit mode or in Display mode

You create a custom page layout that contains code-behind. You need to identify whether the
page is in Edit mode or in Display mode. What should you use?

A.
SPContext.Current.ListItem.Properties

B.
this.Form

C.
SPContext.Current.FormContext

D.
this.Web.ASPXPageIndexMode

Explanation: