[phs318u]

Let me rephrase your first (b).

b) a set of banks who were willingly ignorant that they were lending to a state with a history of bankruptcy over many decades, because they believed/knew that when push came to shove the EU (taxpayers) would bail them out (which they did. You realise that the Greek "bailout" was a bailout of the EU banks that lent to the Greek state).