Why is a fundamental understanding of the forces that promote the development of cities necessary for understanding real estate markets?

		It is not really important for understanding real estate, but it is an interesting history lesson.
		Cities are important for military strategy, the most important aspect of real estate.
		Cities facilitate trade, and real estate is a tradable sector because of things like REITs.
		Space is scarce in cities so understanding them helps in understanding the demand for space.
		None of the above.