Which payment method would be most appropriate during the transition?

You are transitioning from a traditional "brick-and-mortar storefront that accepts credit cards to a new e-commerce storefront. Which payment method would be most appropriate during the transition?

A.
Cash on delivery (c.o.d.)

B.
Credit card with offline processing

C.
Advance payment using check or money order

D.
Open Buying on the Internet (OBI)