awkward question: "Eventually, globally, 'z' holds is necessary for 'n' holds"

[bennn]

The wording of this question is awkward. I'm not sure what it's looking for:
"Eventually, globally, 'z' holds is necessary for 'n' holds"

And then, based on the commas, I guess the answer should have the form "F(G(_))" for some _ that says z is necessary for n. But none of the options have that shape!

The correct answer is (F (n -> (G z))) ... and I'm not sure how to describe this cleanly in English.

[sidprasad]

I also assumed that the answer would be F(G(n ->z)). Comma seems like a bad choice here.
I think this is related to #10