Which of the following statements about local roads is true?

The statement regarding local roads making up nearly 69% of the system mileage is accurate because local roads serve as the vital connections within communities, allowing for access to residences, businesses, and other services. They represent the largest portion of the road network in terms of mileage due to their prevalence in both urban and rural areas. This high percentage illustrates the significant role local roads play in everyday transportation, as they accommodate a substantial amount of local traffic.

The other statements, while they indicate important aspects of road usage, do not provide a comprehensive or accurate view of local roads. For instance, local roads do not necessarily carry over 15% of the travel; in fact, a significant portion of travel may be attributed to higher-capacity roads. Similarly, while local roads exist in urban settings, they are not exclusively urban, as they are also found extensively in rural areas. Therefore, confirming the specific aspect of local roads making up nearly 69% of the system mileage highlights their extensive reach and importance in regional transportation networks.