Which of the following is a condition for a U.S. citizen to qualify for the foreign earned income exclusion?

To qualify for the foreign earned income exclusion, a U.S. citizen must indeed reside in a foreign country for an entire tax year, which is why this option is correct. The foreign earned income exclusion allows eligible taxpayers to exclude a certain amount of their foreign earnings from U.S. taxation.

Residing in a foreign country for an entire tax year satisfies one of the key requirements for claiming this exclusion under the physical presence test or the bona fide residence test. Meeting this condition demonstrates that the taxpayer is living and working abroad, which is essential for establishing eligibility for the exclusion of foreign earned income.

The other conditions, while they may play a role in overall tax considerations, do not specifically satisfy the requirement for this exclusion. For instance, spending at least a certain number of days abroad might seem relevant, but it does not directly correlate with the entire tax year residency requirement. Being a citizen of a nondesignated country is also irrelevant, as the exclusion applies regardless of the country designation, as long as residency criteria are met. Maintaining a foreign bank account may be a good financial practice when living abroad, but it is not a condition for eligibility regarding the foreign earned income exclusion.