Definitely “country's” is the singular possessive. Country is singular. Countries means many countries, therefore plural.
In this regard, what is the possessive of country?
Singular and Plural Possessive Nouns
Subsequently, question is, is Country singular or plural?
Basically in English, there is a group of nouns which can be either singular or plural depending on what you want to say about them. So for example, if we're looking at the United States the country we would normally use the singular verb so for example – “The United States is a very big country.”
What are 15 world countries?
Alphabetical list of countries
Is England a country?
England is a country that is part of the United Kingdom. It shares land borders with Wales to the west and Scotland to the north. England is separated from continental Europe by the North Sea to the east and the English Channel to the south.