Country provides a select box of country names based on ISO 3166 Country codes.
The plain preset:
<cf_terrafield preset="country" name="MyCountry1" />
Set Spain as the default and make it a required field:
<cf_terrafield name="MyCountry2" caption="country (2)" preset="country" default="ES" required="true" />
Use checkboxes to allow multiple selections:
<cf_terrafield name="MyCountries3" preset="country" caption="countries (3)" format="checkbox" />
Fields marked with * are required.