In the Gospel of John, Jesus performs several 'signs.' Beyond their immediate impact, what is the overarching purpose of these signs as presented by John?

A To demonstrate Jesus' power over nature and disease, proving his divine status. B To compel people to believe in Jesus through miraculous displays of authority. C To reveal Jesus' glory and point to his identity as the Messiah, leading to faith and eternal life. D To alleviate suffering and provide temporary relief from the hardships of earthly life.