In a question like this, it seems to work out best if the reader is able to determine what constitutes importance and the selection of scenes is based off of this. In Wiesel's work, there seems to be so many important moments where so many truths are revealed about Eliezer's belief systems and his experiences in the Holocaust. One could argue that the moment back in Sighet, where the villagers reject Moshe the Beadle's claims about what he experienced would be a critical moment because it reflects the denial and silencing of voice on the part of the victims which helps to embolden the aggressors. At the same time, Eliezer's experiences at Birkenau could be deemed as "important" because Eliezer rejects the presence and benevolent force of God when he sees babies and children incinerated at the hands of the Nazis. It is also an important moment because Eliezer is separated from his mother and sister. While there are so many important moments, I would think that the child's execution at Buna could be another important moment because it is at this moment where Eliezer's complex approach to the divine is revealed in the quotation, "God is in the gallows." Again, to find three important scenes is both easy and difficult because there are so many moments in the essential realm and difficult to make a choice from such powerful ones.