A technical support engineer receives a ticket from a user who is trying to create a 1KB file in the /tmp directory and is getting the following error: No space left on device. The support engineer checks the /tmp directory, and it has 20GB of free space. Which of the following BEST describes a possible cause for this error? 

Answer options:

A. The /tmp directory is not mounted.
B. The filesystem is formatted with a 4MB block size.
C. the filesystem ran out of inodes.
D. The /tmp directory has been set with an immutable attribute.

C

Reference: https://www.maketecheasier.com/fix-linux-no-space-left-on-device-error/