Refer to the exhibit. This network has two connections to the ISP, one via router C and one via router B$.$ The serial link between router A and router C supports EIGRP and is the primary link to the Internet. If the primary link fails, the administrator needs a floating static route that avoids recursive route lookups and any potential next$-$hop issues caused by the multiaccess nature of the Ethernet segment with router B$.$ What should the administrator configure?