The correct response is "inability to make an error". Conor's sense of his own infallibility means that he believes he cannot make mistakes or errors in his chess game. This mindset can contribute to his success because it gives him confidence and allows him to make bold and decisive moves without fear of making a wrong move or losing the game. However, it's important to note that this response is subjective and could vary depending on the individual and their playing style. To determine the specific factors contributing to Conor's success, it would be helpful to analyze his competitive nature, open-mindedness, and strategic skills as well.
