Which One of the Following Statements Regarding Backup Strategies for Java

Which one of the following statements regarding backup strategies for Java files is correct?

A) You should have multiple copies of your source files in different locations.
B) You should regularly print out your work so you can retype it in case of data loss.
C) You should regularly back up the Java virtual machine instructions to prevent loss of valuable work.
D) Your compiler automatically makes backups of your source files.