My tax resident status

Hi, I am a foreign national who became a resident alien in 2020. My question is, I lived in NY, MA and KY for 2020 but for 90 days each (so 270 days approx in total in the US). But I was not a resident of any of these individual states by Dec 2020 (I pay rent in MA since September though, but I went back abroad for all of December). When the tax form asks me what state I was a resident of in Dec 2020 and if I lived in another state, should I just mention 'foreign'?