What proves this? The very first civilizations we know of from ancient Egypt and ancient Mesopotamia have religion as a fully-blown developed concept...
with very well-developed theologies, rituals, ethical systems, and even institutions. There is no evidence for the "evolution" of religion...
Jesus said that He alone was the way, the truth, and the life (John 14:6) Therefore, Jesus said all other systems are false. Does this sound reasonable to you?
If the person asks where's the proof for God/Jesus/Christianity, go here.