The correct option is B agree
The infinitive verb is a verb with the word 'to' in front of it. Out of the four options, option B is correct. Accept means consent to receive or undertake. Comply means act in accordance with a wish. Concur means be of the same opinion. Agree means doing something which has been suggested by other person. All options don't fit with the meaning of sentence except option B. Thus, 'agree' is the correct answer.