Normally your pen drive remains in FAT or FAT-32 file system format.And when you will intend to format your pen drive in NTFS file system, you will see only FAT and FAT32 formatting option. Like this picture below
Now check the "optimize the performance" option and leave by clicking ok.
Now go back to your pen drive formatting and you will be able to see NTFS format option along with FAT and FAT32.