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A
Canada
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B
Puerto Rico — and other US territories include Guam, US Virgin Islands, American Samoa, and the Northern Mariana Islands
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C
Mexico
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D
Cuba
Why this is the answer
US TERRITORIES are areas under US sovereignty that are not states. Residents of territories are US nationals (and most are US citizens by birth) but territories do not have full Congressional voting representation and their residents cannot vote in presidential elections while residing in the territory. THE FIVE INHABITED US TERRITORIES: Puerto Rico (Caribbean, most populous territory); Guam (Pacific); US Virgin Islands (Caribbean); American Samoa (Pacific — residents are nationals, not automatically citizens); Northern Mariana Islands (Pacific). USCIS Question 92: 'Name one US territory' — any of the five above is a correct answer.
Source: USCIS Civics Question 92 — US Territories