A National Advertiser Would Like to Advertise More in Newspapers,but

A national advertiser would like to advertise more in newspapers,but there is a substantial rate differential between national advertisers purchasing the same ad size as local retailers.On average,the national advertisers must pay more than 60 percent more for the same space.What can a national advertiser do to avoid this rate differential?

A) Use the "one-order, one-bill" ordering system because they've negotiated the rates down to the local rates.
B) Use the "co-op" ordering system because they've negotiated the rates down to the local rates.
C) Advertise only in larger cities because newspapers in those markets do not charge a rate differential.
D) Use co-op advertising, which is an arrangement between an advertiser and a retailer whereby the retailer buys the ad at the local rate and the advertiser reimburses some or all of the costs.
E) There's really nothing a national advertiser can do to avoid the higher rate.