I want to create a cell data validation input based on a list but make it
conditional on a yes/no selection

Example, two columns :

Col A Col B
-------- ------------
Yes Prod x
No Item a
No Prod f
Yes Item g
No item b

The above lists are variable and cannot be sorted, but have assigned range
names, rngYesNo = a1:a5, rngList = b1:b5.

What I am trying to do is create a cell data validation elsewhere in
worksheet which will only show the items in rngList which have a Yes in
column A ; so in the above example it would only show Prod x and Item g.

thanks,
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Regards & Thanks