B. Humans have interesting brains that do many things to memories.
Explanation:
When reading the text, it mentions several times that our brains alter our memories, supporting letter B, that our brains' do many things to our memories. You can also use process of elimination: A is incorrect because it doesn't mention anything about remembering early memories. C is incorrect because even though it gives an EXAMPLE about remembering a room, that isn't the main focus.
