Could an American President Decide, Unilaterally, to Recognize a Breakaway

Multiple Choice

Could an American president decide, unilaterally, to recognize a breakaway or secessionist country's legitimacy by receiving its emissaries, even if the country it broke off from objected?

A) Yes, since as head of state, presidents may receive foreign ambassadors and ministers
B) Yes, since presidents would be able to do so through executive orders to the State Department
C) No, since Congress must formally recognize foreign states before presidents may meet with their foreign representatives
D) It depends on whether the Supreme Court insists on having a say in the situation.