Can ransomware hijack Mac backups? Yes, but...

Mac users have so far avoided the scourge of ransomware sweeping the Windows world, where it’s the fastest-growing category of malware due to its simplicity: it encrypts your documents after gaining a foothold to run, and doesn’t have to mess with system-level stuff at all. Reader Dave has a concern related to backups though, after reading my recent article about the best hosted backup services for encrypted protection:
If I am primarily worried about ransomware on my Mac, which of t