Desired Min TX Interval: This is the minimum interval, in microseconds, that the local system would like to use when transmitting BFD Control packets, less any jitterapplied. The value zero is reserved.
Required Min Echo RX Interval: This is the minimum interval, in microseconds, between received BFD Echo packets that this system is capable of supporting, less anyjitter applied by the sender. If this value is zero, the transmitting system does not support the receipt of BFD Echo packets.

In EIGRP (Enhanced Interior Gateway Routing Protocol), a stub router is one that is connected to one or more neighbors and should not be a transit router1. The EIGRP stub routing feature improves network stability, reduces resource utilization, and simplifies the stub router's configuration1.
The network engineer wants to configure an EIGRP stub router that advertises only connected and summary routes. This can be achieved with the configuration provided in Option B:
router eigrp 100
eigrp stub summary
This configuration ensures that the EIGRP stub router advertises only connected and summary routes12. The summary keyword after the eigrp stub command indicates that the router should advertise only auto-summarized or statically configured summary routes12.
References:
* EIGRP STUB and Configuration - Cisco Community
* EIGRP Stub And Summary Routes Explained - Networkel