Am I right in concluding that only one of these can resolve yes? So they are actually dependent?

Multiple answers can be chosen.

So the crises need to pass some threshold to resolve yes? Under what circumstances would “no crisis” resolve yes along with some others?

If there was no crisis, then only no crisis will the answer.

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This question is subjective and will likely rely on several heuristics to resolve:

• Did the economy / stock market react negatively in a significant way?

• Number of lives lost

• Financial cost

• Did the government use significant amount of resource to manage the crisis? For example, draw on reserve.

• Has the event stayed in media headline for several weeks / months?

• Is there a Wikipedia article about the event?

“””

Does the currently ongoing oil spill count as an industrial accident?

Yep. Or do you think I should add a new category?

No, seems right to me