Who assigned Cut, Copy, Paste, and Undo to X, C, V, and Z?

Why does it matter ?

Not sure but they make sense in proximity to ctrl (at least on a US layout). and further, the characters make sense. X looks like scissors in open position, c for copy, v as a carrot pointing where you want stuff...z is in the shape of putting somthing back from a slice of memory if you stretch your imagination.