The most appropriate backup method for a company that wants to ensure data encryption and accessibility from any location at any time is cloud backup. Cloud backup solutions provide remote, offsite storage that can be accessed over the internet, which is ideal for ensuring data availability and security. These solutions often include robust encryption protocols to secure data during transfer and while at rest on the cloud servers. This aligns with the need for a backup method that not only encrypts data but also allows for easy access regardless of the user’s location.

References: The explanation is based on standard practices in data backup and security, which are consistent with the objectives and documentation of the Certified Network Defender (CND) course. Cloud backup is widely recognized for its encryption capabilities and remote accessibility, making it a suitable choice for companies looking to secure their data backups.