The correct answer is " The Louisiana Purchase". The ability to buy property from foreign governments was not among these powers listed in Article IV of the Constitution – a fact that his political opponents, the Federalists, were eager to point out to the President Thomas Jefferson. According to Constitution Daily website - "Jefferson rationalized his decision for the treaty to be sent to Congress without an amendment to John Breckinridge. “It is the case of a guardian, investing the money of his ward in purchasing an important adjacent territory; and saying to him when of age, I did this for your good,” he said in August 1803". Jefferson and his supporters faced an October 31, 1803 deadline to ratify the treaty or lose the purchase. Ironically, the deal to expand federal powers would need to be sold to the Federalists, who had advocated such a position before the treaty was signed, and supported by the Republicans, Jefferson’s party, which had opposed such a broad extension of presidential powers. The debate in the Senate only lasted for two days. On October 20, 1803, the Senate voted for ratification 24-7, and the treaty was signed on October 31, 1803. In the treaty’s aftermath, although some Federalists continued to view the Louisiana Purchase as unconstitutional, the purchase was never questioned in court.
The second alternative is correct.
The American Constitution does not approve the purchase of other countries institutionally. However, President Thomas Jefferson made a treatise on negotiation. And executing treaties is a constitutional power of the president of the Republic.
