While New York City's population is more than twice as large as the 2nd largest American city, Los Angeles, which statement best explains why the United States does NOT have a primate city?

This is because despite being the largest city in the country, New York City only has around 6% of the total U.S. population when its metropolitan area is taken into account.

A primate city, on the contrary, is a city that has 20%, 30% or even 40% of the total population of the country, regardless of how much larger it is than the second city.