The first step in answering this question is to ensure that you understand the contents of the treaty and the subsequent impact on instability. For example how the huge war reparation payments were devastating to the German economy and thus caused serious instability… After this you will need to find some counter arguments, these could really be anything that you feel you have the evidence to argue your case. As long as you can find a logical chain of argument you will be fine! I would recommend looking at the roles of the extreme right and left as well as long term economic problems. The tricky part of this question is how you structure it. As usual you need to start by introducing your argument in the introduction, what this will be of course depends on your personal views and what evidence you have at your disposal. In any case, what you choose to argue is actually not that important, what matters is that you can argue it. In the main body of your essay the best place to start would be to make a case for why Versailles contributed to the instability, since it is named specifically in the question you have to devote a fair amount of attention to this, examples of what you discuss include the feeling of betrayal and the occupation of the Ruhr that resulted from the treaty. After this is where the essay becomes tricky, if you believe Versailles to be the main cause of instability then you will need to demonstrate that there are alternative causes but that you still believe them to be less important. For example, the Munich Putsch of 1923 may have been very significant in causing instability, but would likely not have occurred without the occupation of the Ruhr. If you choose to argue that Versailles was not the main cause then this is where you bring out your argument and make the case for what you believe. This need not be one other factor, one argument could be that all of the causes were too interconnected to allow for one main cause. The final thing to remember is to look at the links between the different causes, this is what separates the top grades. Look at how the extreme right and left used Versailles and the economic problems to their advantage. Some people choose to do this in their conclusion but this is not the best idea, for the strongest essay possible you should be making links between pieces of evidence throughput your essay. Last but not least you need to conclude your argument, this is the easy bit, all you need to do is reiterate your main argument and sum up what you have argued.