You need to send the action along the responder chain, starting with the "first responder". Try this:
[[UIApplication sharedApplication] sendAction:@selector(cut:) to:nil from:self forEvent:nil];
If you have the UIEvent that triggered the action, you might pass that as the last parameter.
You can read about the responder chain in Event Handling Guide for iOS: Event Delivery: The Responder Chain.
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