I also believe that strategic bombing was the most important contribution to victory. It is very important that we include all causes, V-E was not mono-causal, so stay away from that argument. However, if you must choose one single important factor and prove that it was the most important factor, strategic bombing would not be a bad choice. However, you must legitimize it by looking at the other causes and why they are not as integral. The failure of the Italian military is an overlooked cause of defeat for the Axis in Europe. What began as a relief and reinforcement effort in North Africa turned into a huge momentum shift for the Allies. Likewise, the production rates of the USSR and the United States surpassed that of Germany. Germany began the war with more materiel than any other country, but eventually could not contend with the production of the USSR and the United States. While Germany's equipment was generally more advanced and better than the Allied equipment, there were less of it.

Strategic bombing, especially daylight raids that were escorted by the P-51 well after the Casablanca Conference, only worsened Germany's production inferiority. Targets such as Schweinfurt's ball bearing factory, Augsburg's Bf 109 factory, Oschersleben FW 190 factory, etc. were hit hard and often. Eventually, the Luftwaffe's ability to defend faded as production was nearly halted due to bombing raids. Some factories were built underground to avoid bombing.

My final point to make is that you must make a decision. Which was a more significant cause, production or strategic bombing? Are they a manifestation of each other or are they separate? Something to think about good luck on your paper.