Please refer to my comment in your Netherlands quiz about the definite article. IMO no city begins with one. Therefore El Paso starts with a P and Los Angeles with an A.
I disagree. Because it's the name in English borrowed from Spanish, El Paso and Los Angeles are usually considered single names, not definite article+main name. I think they should remain the way they are. I would regarding the Netherlands quiz, this is true since it is the Hague in English, not Den Haag, but the same cannot be said of El Paso and LA