Which of the following must be true for two EIGRP routers to become neighbors?

For two EIGRP routers to become neighbors, they must belong to the same Autonomous System (AS). The AS Number (ASN) is a fundamental parameter in EIGRP configuration, defining the scope of the EIGRP routing domain. Without a matching ASN, routers will not exchange EIGRP hellos or form neighbor relationships. While identical hello and dead timers are generally recommended for optimal convergence, EIGRP can still form neighbors with mismatched timers (though it may lead to suboptimal behavior). Unique router IDs are necessary for loop prevention and identifying routers within the EIGRP domain, but not for initial neighbor formation. Matching MTUs are crucial for avoiding fragmentation and ensuring efficient packet forwarding, but EIGRP neighbor adjacency can still be established even if MTUs differ.