I think the confusion here is the term "dynamically exchange information", because it does not make it clear if they are taking about 'routing information' or pure 'data information' e.g a user sending an email.
Reading furthermore... 'administrator must configure at least one router with a default route'. This then makes everything clear. We know that if you want your router to exchange routing tables dynamically, that is, with the use of a routing protocol, you must enable the routing protocol process (e.g #router rip - to enable the Rip routing protocol). Since it mentions as a minimum configuration ' at least one default route' then it's clear that it is talking about the exchange of real user data e.g web, email e.t.c.
So, taking in consideration all the above, the statement is correct as you do need at least one default route in your router's routing table for it to send/receive data to and from networks beyond your local LAN.
If anyone has other suggestions, we would like to hear them.
cheers,