Broadband is to dialup what interstate highway is to:

Highways and interstates would most likely be referring to you traditional freeways possibly with two lanes going in apposing directions depending on where you choose to drive you’re vehicle. For if your driving in the cities you’ll be on the freeway which is also considered to be a highway due to a lack of signals and stops; however highways and interstates would be found towards rural areas or close to dirt roads in most cases especially when your driving out near the country. Interstates as well however interstate is also a known company which manufactures automobile batteries as well.

It's most likely choice a, it makes the most sense in my opinion.