for a printjob i used a barcode 128. Now the customer asked me which subset i used: A, B or C???

Does PSM choose itself (automatically) which subset will be used? The datafield to be 'barcoded' consists of 9 numbers. So i think PSM will use subset C, but on the other hand i heared that subset C can not be used for a uneven numbers of characters... (in this case 9 numbers).

Can somebody let me know how PSM defines the subset, and if 9 numbers can be used for subset C? And otherwise which subset would be used?

Thx a lot!