$1$ pts

Pitt Fitness is now routinely creating backups of their database. They store them on a server and have a number of backup files that need to be deleted. Which of the following files is the correct backup and should not be deleted?

PittFitness$\_2021-11-27$

PittFitness$\_2021\mathrm{.}08-12$

Pittfitness$\_2021-10-31$

PittFitness$\_2021-09-30$