Priority Rules / Column in Table Visualisation

Brian415_ 

Create a dedicated table with unique values of product and do not create any relation between product list table and the actual data table. Put the product column from product list into the slicer create a measure using the below pattern.

Condition_Check = 
Var SelectedProductCategories = CALCULATETABLE(VALUES('Data Table'[Category]), 'Data Table'[Product] = SELECTEDVALUE(ProductsTable[Product]),  ALLSELECTED('Data Table')) 
Var __Condition = SWITCH( TRUE(),
    COUNTROWS( EXCEPT(SelectedProductCategories, {"A"})) = 0 , "A",
    COUNTROWS( EXCEPT(SelectedProductCategories, {"A","B"})) = 0 , "A",
    COUNTROWS( EXCEPT(SelectedProductCategories, {"B"})) = 0 , "B",
    COUNTROWS( EXCEPT(SelectedProductCategories, {"B","C"})) = 0 , "B",
    COUNTROWS( EXCEPT(SelectedProductCategories, {"C"})) = 0 , "C"
)
Var result = IF(SELECTEDVALUE('Data Table'[Category]) = __Condition && SELECTEDVALUE(ProductsTable[Product]) = selectedvalue('Data Table'[Product]), 1, 0)
return result 

 You should use this meausre as a visual lelvel filter. I am attaching the file for your reference.