Answer: Allied appesement was the most nessicary condition for WWII
Explanation: This can be debated. To support that appesement was the most nessicary condition, you can say how because the allied powers appesed to Germany's requests, Germany was able to gain more land and influence, growing its power. If Nevile Chamberlain didnt appese and allow Germany to take land, maybe the war would never been fought.
I hope that helped;)