What does it mean to refuse stubbornly and abruptly?

To refuse stubbornly and abruptly means to balk. This term specifically encompasses the idea of resisting or rejecting something in a way that is both firm and sudden. When someone balks, they show an unwillingness to proceed or accept a proposal, often indicating strong opposition or dissent. This aligns perfectly with the description given in the question, as it highlights a forceful refusal without any interest in negotiation or compromise. In contrast, the other options such as compromise, accept, and concede imply willingness to engage in some form of agreement or acceptance, which directly contradicts the essence of balking.