What is the number 1 classic movie?

I'm curious, could you elaborate on what makes a movie a "classic"? Is it based on popularity, critical acclaim, or cultural significance? And furthermore, if we're discussing the number 1 classic movie, how do we objectively determine which film tops the list? Is it a matter of personal preference, or is there a consensus among film experts and enthusiasts? Additionally, are we talking about a specific genre, or is the question open to all types of films? I'm eager to hear your thoughts on what constitutes the number 1 classic movie and why.