The actual question asks whether or not you agree with the quotation. You need to demonstrate knowledge of both sides but must ultimately come to a clear judgement.The quotation refers to Germany's 'blank cheque'. You should explain clearly what this is but most of that will come in the analysis so that you don't waste time on description.The quotation suggests this factor is 'the most important'. Obviously, you need to judge how far it is important and how far it is not but you can also consider other factors.You also need to bear in mind the reference to 'a general European war'. What was the link between the 'blank cheque' concerning Austria-Hungary's actions in the Balkans and the subsequent escalation of the war?Firstly, then, you can consider why the 'blank cheque' was important.Austria only felt strong enough to act with German support.The support that Germany offered had no stipulations which gave Austria great freedom.Germany already had plans for war (Schlieffen Plan, pre-emptive war against Russia) and 1914 was their best chance at this, explaining the extent of German support.Secondly, consider why the 'blank cheque' was less important.It is possible that this was simply intended to scare the Russians off (they had not acted in 1908) rather than provoking war.With that in mind, was it Russia's mobilisation that really triggered the war?Finally, was it not the alliance system that caused 'the general European war' bringing in Britain and France.In conclusion, you need to decide which side you fall on. The question asks you if you agree or disagree. Either is fine but it should be clear and ideally nuanced.