Answer Description

FAT32 is an older format that is supported on most systems, and is the best option provided. NTFS may cause issues between systems and OSs. HFS+ is the native OSX format and is not natively supported by some OSs (to include Windows). AES-128 is an encryption standard.

Wikipedia

File Allocation Table (FAT) is a file system developed for personal computers and was the default filesystem for MS-DOS and Windows 9x operating systems. Originally developed in 1977 for use on floppy disks, it was adapted for use on hard disks and other devices. The increase in disk drives capacity required three major variants: FAT12, FAT16 and FAT32. FAT was replaced with NTFS as the default file system on Microsoft operating systems starting with Windows XP. Nevertheless, FAT continues to be used on flash and other solid-state memory cards and modules (including USB flash drives), many portable and embedded devices because of its compatibility and ease of implementation.