Final answer:
To protect against accidental deletion, duplicating the file and storing it in a separate location is the best option among the ones provided. It creates a backup that can be restored if the original is lost.
Step-by-step explanation:
To ensure maximum protection and prevent the accidental deletion of a preserved version of a file, the best option from the ones provided is to duplicate the file. When you duplicate a file, you create a copy of it, which can be stored in a different location, such as an external hard drive or cloud storage. This method is also known as creating a backup. If anything happens to the original file, you will still have the copy to restore from. It's important to keep the duplicated file in a separate location to protect it from the same events that could compromise the original file, such as hardware failures, malware attacks or accidental deletion.
While sharing the file with multiple users could theoretically distribute the risk of data loss, it also increases the risk of the file being modified or deleted by others. Encrypting the preserved version is vital for security purposes, but it does not protect against deletion. Reducing the file size might make the file easier to transmit or store, but it does not protect against deletion either.