What Solution Did Conciliarists Advance to End the Conflict Among

What solution did Conciliarists advance to end the conflict among the multiple popes and their competing claims to legitimacy?

A) They argued that a general council of the church would best hear God rather than one individual.
B) They contended that since their members represented both spiritual and secular authorities, they had a stronger claim to legitimacy than any one pope.
C) They claimed that all previous major decisions affecting the church were made by church councils, not an individual pope.
D) They argued that their council had never communicated with Muslim authorities, but the divisive popes had done just that.
E) They devised a formula that calculated that the cardinals', bishops', and others' votes outweighed the vote of any one pope.