Answer:
Paragraph 3, the importance of memory in recalling what can be rather than what is.
Why:
Wiesel's number one intention with his book is to let the people in the world know the atrocities that took place in those concentration camps. This is a man's call to humanity to not make this mistake ever again.
He intends to achieve this by exposing detailed acts of cruelty carried out by Nazi soldiers in their concentration camps. He is as well exposing the human being's intolerance and inhumanity towards another human being. This is accomplished when Eli describes awfully himself as "a stomach" because of his severe hunger and deprivation.