What are some characteristics of a suspicious vehicle that can change?

The correct choice identifies specific characteristics of a suspicious vehicle that can frequently change or be modified. Items such as bras or deflectors, hubcaps, and decorations hanging from the rearview mirror can easily be added, removed, or altered by individuals. This makes them dynamic indicators of suspicious behavior, as the presence or absence of such items might signify an attempt to conceal identity or intentions.

In contrast, elements like engine type and color, license plate state and make, or year of manufacture and size tend to be more static. These features are generally fixed once a vehicle is manufactured and registered, making them less likely to change with time or in suspicious circumstances. The dynamic nature of the items in the correct choice highlights their relevance in monitoring potential security threats, as they can indicate recent modifications that may not align with typical behavior for a particular vehicle.