nested data validation in excel without macro?

sheet 1 Sheet 2
A 11 A 101
B 22 B 202
C 33 C 303
D 44 D 404

In Sheet 3
A1 cell have drop down list of sheet 1 & sheet 2 name.
when any of sheet selected, below table should have respective data validation.
try to create an invoice where each customer have different rates for the product

Hi,
I hope the attached excel is what you require.
But there is a minor issue in the above data validation. The problem is auto refresh.
That is when you make a selection say Sheet1 and then you select 11.
Next when you select Sheet2, the datavalidation cell will still show 11. Only when you select the dropdown will you see the required values for Sheet2. So there may be chances of error if you forget to click the concerned datavalidation dropdown.
For auto clearing of the dependent data validation, I believe macros need to be used. If any other solution exists, I am unaware of the same.