8 Pieces of Evidence:
1. What did Austria do to start the war?
Austria was the first country to declare war. Austria declared war on Serbia when the Archduke, Franz Ferdinand, is assassinated by a Serbian-trained terrorist. After Austria declared war, many other countries ended up joining the war because they were either allies with Serbia or Austria. Germany joined to aid Austria, which ultimately lead to Germany declaring war on France and Russia, who were allies with Serbia. This is how Austria-Hungary is at fault for starting World War I.
Source of evidence: http://www.firstworldwar.com/features/balkan_causes.htm
2. What did Germany do to contribute to the war?
As mentioned above, the event that sparked World War 1 was the assassination of Franz Ferdinand. As a result of his assassination, Austria declared war on Serbia. Germany played a huge role in this descision, as Germany influenced Austria to start the war. Germany gave Austria a blank cheque which helped them fund their war needs. Knowing that Germany is going to support them, Austria felt more confident in starting war. So, Germany is to blame for World War 1 because Germany greatly influenced Austria into starting war.
Source of evidence: Source A
3. What did France do to contribute to World War 1?
In World War 1 France wanted to take revenge on Germany. This is because in the 1800's Germany played a crucial role for the defeat of Napoleon. Once Russia declared war on Germany, France found an oppertunity to get revenge. France sent Russia a blank cheque, which Russia used to build a railroad along the German border. Germany, knowing that it would soon have to face war on two fronts, attacke France through Belgium. This proves that France is to blame for World War 1, because France's actions forced Germany to attack them.
Sources of evidence: Source J
http://wiki.answers.com/Q/Why_did_France_want_revenge_on_Germany#slide=6&article=Why_did_France_want_revenge_on_Germany
4. What did Russia do to start World War 1?
In World War 1, Russia was the first to mobilize. This caused Germany to feel threatened and counter mobilize to avoid a two-front war. The Germans activated the schlieffen plan and war was soon to begin. If Russia hadn't mobilized, the Germans wouldn't have reacted with the schlieffen plan and the war wouldn't have begun how it did, and possibly not begun at all.
Sources of evidence: Source J and http://www.historyplace.com/worldhistory/firstworldwar/index-1914.html
5. What did Britain do to contribute to the war?
Britain: Britain could've prevented the WWI by confirming what position they were taking; whether it was with the Triple Entente, Triple Alliance, or remaining neutral. If they declared to stay neutral, the other countries would've been more cautious to start war since Britain would most likely take the victim’s side. If they stated what alliance they were going to be a part of, it would've stop the countries from attacking one another. By being unclear, Britain did not prevent World War 1.
Sources of evidence: Source H
6. What did Serbia do to start the war?
As mentioned above, the event that really started the war was the assassination of Franz Ferdinand. The assassin who killed the Archduke was a Serbian trained terrorist. Once Austria found out about this, they demanded to Serbia to let them in and kill the terrorist. Serbia refused, and as a result, Austria declared war on Serbia. So, Serbia is also at fault for starting the war because they trained assassins, one of which killed the Archduke. Also, Serbia refused Austria-Hungary's demands, which is the reason why Austria declared war on Serbia.
7. What did Alliances do to start the first world war?
Alliances played a key role in the start of World War 1. When two people got into a fight, more than just the two of them got involved. When the archduke of Austria was assassinated, the Austrians attacked the Serbians. The Russians got involved and Germany attacked France also invading Belgium in the process. Since France and Russia were allies, they declared war against Germany, and Britain being allies with Belgium, also joined in and declared war on Germany. IF there were no alliances, Serbia and Austria could have easily cleared it all up and no war would have occurred.
Sources of evidence: http://www.ask.com/question/how-did-alliances-contribute-to-the-outbreak-of-world-war-i
8. What did Italy do to contribute to the War?
Italy was one of the countries that sided with Germany. By doing this, Italy allowed the Triple alliance to maintain equal power with the Triple Entente. By doing this, it allowed Germany to attack France knowing that there was no disadvantage in forces towards Germany. This is how Italy contributed to World War 1.