What must a driver remove from an unattended vehicle according to New Hampshire laws?

Answer: A — The key

In New Hampshire, it is required by law that a driver must remove the key from an unattended vehicle. This regulation is primarily in place to prevent auto theft and ensure the safety of the vehicle. Leaving the keys in an unattended vehicle increases the risk of unauthorized usage, which can lead to theft or accidents. By removing the key, the driver significantly decreases the chances of the vehicle being stolen or misused while it is unattended. Other options, such as leaving the insurance card, registration papers, or a spare tire in the vehicle do not have specific legal requirements for removal when leaving the vehicle unattended. While it is advisable to keep important documents secure and not visible in a car to prevent theft, they do not pose the same immediate risk of facilitating vehicle theft as leaving the key does.