Despite this question is rather old, it’s rather cool as well.
So, let me ask a question thereon.
The answer to (b) part has nothing to do with multilateral netting: the balances in EUR and USD are separately netted, which is efficient and smart in this case.
The part (c) asks to produce a paper justifying the proposed strategy. The answer describes features of multilateral netting. Though, this does not comply with the part (b).
Am I correct (or netting balances in the same currencies between several companies is also a kind of multilateral netting)?