Hi ellenb,
Quickly reviewing that last sentence, shortening "Volitional Power" for easy reference:
Computers do not have V-power...
Computers
V-power
V-power
Computer
...although some non-human animals have V-Power:
non-human animals
V-power
So, all we know is this: there is are some (that is, at least one) non-human animals that have V-power.
The only non-animal we have been told anything about is the computer, which doesn't have V-power.
...But that doesn't necessarily support B, which refers to non-animals in general (that is,
all non-animals).
So, again, we know that
computers don't have V-power, but that still leaves the possibility that there are other non-animals that do.
I hope that's helpful! Please let me know whether this is clear--thanks!
~Steve