Using apostrophes

Some simple apostrophe rules

• A plural, such as "Dogs" to describe many Dogs, uses no apostrophe. For your example, though, the word country becomes countries when describing more than one country (and ending in 'y' becomes 'ies' rule, I think)

• "It's" is a contraction of it is, and so uses apostrophe s

• "Harry's" describes something possessed by Harry, e.g Harry's foot.

  This can be a tricky one to remember, as it is a contraction of "Harry his (foot)" (a term that is never used any more in its expanded sense), and country's is also a contraction of the odd sounding "country his (or hers)". As this is a contraction, we use apostrophe s

  Using this rule we see that you are correct in using "country's"

• Charles' describes something possessed by Charles (abbreviation used instead of Charles's) If you don't want to use s's, then we use s apostrophe

• "Its" is the exception to the possession (apostrophe s) rule, presumably as "It his" is a contradictory gender statement, so use no apostrophe

Your use of the apostrophe in "the country's best pizza" is correct. But it is all wrong as regards punctuation and capitals.