What are the three options one had to get to America from Zambales at the time that Vargas's grandparents immigrated?

The three primary ways to get to the U.S. were to join the Navy, to marry a U.S. citizen, or to get petitioned by a relative. Lola Florie was able to immigrate after marrying a U.S. Marine. Later, she was able to petition to bring Lolo to the U.S.