61551
In the 1960 s , because the majority of the residents of the federal capital were illiterate , the planners of the Mexico City Metro designed a system of unique icons to identify each station in the system in addition to its formal name .
 location: Mexico City Metro
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities: Mexico City Metro 
Answer:
 location: Mexico City Metro