A.Add the ProductSize data table and the ProductSizeDescriptor column to the Product dimension. Set the order of the ProductSKU attribute to the ProductSizeDescriptor column.
B.Add the ProductSize data table as a dimension and then add this dimension to the cube as a Referenced dimension. Set the order of the key attribute of the ProductSize dimension to the ProductSizeDescriptor column.
C.Add the ProductSize data table and the ProductSizeDescriptor column to the Product dimension. Create a user-defined hierarchy that has ProductSKU as the top-level attribute and ProductSizeDescriptor as the bottom-level attribute.
D.Add the ProductSize data table as a dimension and then add this dimension to the cube as a Referenced dimension. Create a user-defined hierarchy within the ProductSize dimension. Set the ProductSizeDescriptor attribute as the top-level attribute.