Simplify the following text for a Grade 6 native English-speaking person.
Original: The bells of the Clock Tower in London 's Palace of Westminster are tuned to the key of E major , with the result that the Westminster Quarters in their original setting employ the notes E , F-sharp , G-sharp , and B.
Simplified: The bells of the Clock Tower in London 's Palace of Westminster are tuned to the key of E major .