This experiment will show us _______ can be used in the modern laboratory．

A．that you have invented                    B．how that you have invented

C．that how you have invented'               D．how what you have invented

This experiment will show us ________ can be used in the modern laboratory．

1. A.
   that you have invented
2. B.
   how that you have invented
3. C.
   that how you have invented
4. D.
   how what you have invented