Which of the following statements regarding controlled foreign corporations is true?

Group of answer choices

1. U.S. shareholders are taxable on any income earned by a controlled foreign corporation.
2. U.S. shareholders are never taxable on income earned by a controlled foreign corporation until such income is distributed to the shareholders
3. U.S. shareholders of a controlled foreign corporation can increase their basis by the amount of any constructive distributions from the corporation.
4. Controlled foreign corporations are taxable in the United States on their worldwide income.