Final answer:
The best means of maintaining data security for a lost or stolen mobile device is a Remote wipe, as it completely erases data, ensuring it does not fall into the wrong hands.
Step-by-step explanation:
The best means of maintaining data security for a mobile device that has been lost or stolen would be option C: Remote wipe. This is because a remote wipe allows you to erase all the data on the device, ensuring that sensitive information does not fall into the wrong hands.
Although options such as login attempt restrictions, locator service, and passcode lock provide some level of security, they do not offer complete protection against data theft if the device is not recovered. A passcode lock may prevent a thief from immediately accessing your data, but it can sometimes be bypassed. A locator service can help you find the device, but it doesn't protect the data if the device can't be retrieved. Login attempt restrictions can prevent repeated guesses of a password, but may not stop someone from eventually cracking it or accessing the device through other means.