Final answer:
In ordinary dating method terms, if no net is mentioned with a 2/10 option, it's common practice to assume a net payment period of C)30 days after the invoice date.
Step-by-step explanation:
If no net is mentioned with regard to an ordinary dating method where a 2/10, n/30 option is provided, the common practice is to assume that the net payment date is 30 days after the invoice date. This is because the 'n' in such terms represents 'net' and unless specified otherwise, the net period is typically 30 days. This means the buyer can take a 2% discount of the invoice price if they pay within 10 days, otherwise, the full invoice price is due 30 days after the invoice date.