Final answer:
The configuration of basic NAT on a router with a single default route to the ISP for a small business network with one subnet will allow private network devices to access the Internet using a single public IP address assigned by the ISP.
Step-by-step explanation:
If a student has configured a small business network with a single subnet connected to the Internet and used the SDM interface to configure basic Network Address Translation (NAT) on their router, the most likely result of this configuration is that devices on the private network will be able to access the Internet using the single IP assigned by the ISP. Since only one public IP address is provided, NAT will translate the private IP addresses from the internal network to the single public IP address for outbound Internet traffic. This allows multiple devices on the private network to share a single public IP, which is a common practice for conserving IP addresses and providing a layer of security by hiding internal IP addresses from external networks. A default route to the ISP is necessary to ensure all outbound traffic not destined for the local subnet is sent to the Internet Service Provider (ISP) for proper routing.