What feature improves the JLTV's fuel efficiency?

The choice indicating that an electronically controlled engine and lighter construction materials improve the JLTV's fuel efficiency is correct because modern electronically controlled engines are designed to optimize fuel combustion and enhance performance under various driving conditions. These engines leverage advanced technology to adjust fuel injection and timing, which can lead to more efficient fuel usage compared to older designs.

In addition, the use of lighter construction materials reduces the overall weight of the vehicle. A lighter vehicle requires less energy to operate, which directly contributes to improved fuel efficiency. By combining these two features—an advanced engine and reduced weight—the JLTV is able to maximize its operational range and reduce its logistical burden in the field, making it more effective and economical to operate.