Which answer represents a central idea from Descartes?

All humans are born with a blank slate.

I think, therefore I am.

Our world is the best possible world God could have created.

The material world is not real; we are only thoughts existing inside the mind of God.

Rene Descartes is actually a known mathematician and philosopher and is even dubbed as the "Father of Modern Philosophy". According to him, his main idea focuses on "I think, therefore I am." This statement is translated from his Latin philosophical preposition " Cogito ergo sum". The answer to this would be the second option.