In 2015, U

In 2015, U.S.President Barack Obama and leaders of the United Nations Security Council's other permanent member states signed, along with Germany and the European Union, an agreement with Iran; its goal was to prevent Iran from developing nuclear weapons. While the deal won praise from leaders worldwide, the plan never won majority support in Congress.Congressional division over what to do about the agreement meant, however, that the United States stayed a party to the agreement-at least until 2018, when President Donald Trump withdrew the country from it, without legislative consultation.
Why were Obama and Trump similarly able, despite their opposing views, to act on the Iranian nuclear deal without consulting Congress?

A) The Iran deal was not a treaty but an agreement, and thus not subject to Senate approval, as required under the Constitution.
B) Neither president needed to consult Congress under terms of the Case Act, which governs how presidents may act in making executive agreements.
C) The Supreme Court long ago ruled that presidents do not need to consult Congress in negotiating treaties with foreign states.
D) Neither president needed to consult Congress because party division produced gridlock, a state in which Congress was failing to take action, leaving action up to presidents instead.