Which utility would be used to change how often a filesystem check is performed on an ext2 filesystem without losing any data stored on that filesystem?

mod2fs does not exist as a standard Linux utility.

fsck is used to check and repair a filesystem, not to configure how often checks are scheduled.

tune2fs allows an administrator to change tunable parameters on an existing ext2 filesystem - including the maximum mount count and time interval between forced checks - without touching any stored data. It directly modifies the filesystem superblock metadata, so all user data remains intact. This makes it the correct tool for adjusting fsck frequency settings like -c (max mount count) or -i (interval).

mke2fs creates a new ext2 filesystem, which would destroy all existing data on the partition.

fixe2fs does not exist as a standard Linux utility.