The claim by his followers that Jesus had risen from the dead is not recognized as an undisputed fact about Jesus' life by all scholars due to its nature as a matter of faith and religious belief.
The option from the list which is not among the almost undisputed facts about Jesus' life (held by scholars of all theological stripes) is a - the claim by his followers that he had risen from the dead.
This is because the resurrection is a matter of religious belief and faith, not of historical fact that can be objectively verified. The historical Jesus, his crucifixion, his role as an exorcist and healer, and his baptism by John the Baptist are events that many secular historians would agree on, based on historical documents and records. However, the resurrection is a miraculous event that is central to Christian theology but not universally accepted as historical fact.
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