UIMenuController, Where does it take its target? Confused

When I use a MenuController without any customisation, I would Do this.

UIMenuController *menu = [UIMenuController sharedMenuController];
[menu setTargetRect:self.frame inView:self.superview];
[menu setMenuVisible:YES animated:YES];

menu is a shared instance and I didn't specify the target.

From where the UIMenuController gets the target to perform default actions?