Which of the following vehicles is least likely to have a roll-over protection system?

The reasoning behind selecting the passenger van as the vehicle least likely to have a roll-over protection system lies in the design and intended use of these vehicles. Passenger vans are typically constructed with a focus on interior space and accommodating more occupants, rather than off-road capability or heavy-duty use that often prompts the inclusion of advanced safety features like roll-over protection.

In contrast, vehicles such as SUVs, pickup trucks, and convertibles may incorporate roll-over protection to enhance safety due to their higher center of gravity or specific designs that cater to performance in various driving conditions. SUVs and pickup trucks, which are often used in environments where roll-over potential is a concern, increasingly include systems designed to mitigate the risks of roll-over incidents. Convertibles, although they may have unique structures, can often be equipped with specific safety features to protect passengers in the event of a roll-over, such as reinforced frames.

Thus, passenger vans are generally designed with a different safety focus, prioritizing passive safety features like air bags and crumple zones, making them less likely to come equipped with roll-over protection systems compared to the other vehicle types listed.