Multiple Choice Field Custom Data Rule

Hi,

We have a Multiple Choice field (1) with values "X" and "Y".
And a Multiple Choice field (2) with values  "A", "B", "C", "D" & "E".

We would like to create a Custom Data Rule as follows;

If value the in Multiple Choice field (1) is "X" the values in Multiple Choice field (2) can only be "A", "B","D" & "E" otherwise error message.

If value the in Multiple Choice field (1) is "Y" the values in Multiple Choice field (2) can only be "C", D" & "E" otherwise error message.

Any assistance would be welcome.

Thanks

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Tim Egerton
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