Which command disables auto summarization in EIGRP?

The command that disables auto summarization in EIGRP is "no auto-summary." This command is utilized to instruct the Enhanced Interior Gateway Routing Protocol (EIGRP) not to automatically summarize subnet routes to their classful boundary when advertising routes to other EIGRP routers.

EIGRP supports the concept of auto summarization by default, which can lead to the advertisement of summarization of subnets, potentially causing issues in routing in certain topologies, especially when dealing with discontiguous networks. By using "no auto-summary," a network administrator can ensure that EIGRP will advertise specific subnets, preserving the subnet information and avoiding misrouting in the network.

Other options provided in the question do not correspond to the correct command for achieving the desired effect. Understanding this command is crucial for effective EIGRP configuration and management in various networking scenarios.