When they saw a man blind from birth, what did Jesus' disciples ask him?

Answer: Who sinned, he or his parents?

Jesus answered that neither he nor his parents sinned; it happened so the works of God would be displayed in him.

“Now as Jesus was passing by, He saw a man blind from birth, and His disciples asked Him, “Rabbi, who sinned, this man or his parents, that he was born blind?” Jesus answered, “Neither this man nor his parents sinned, but this happened so that the works of God would be displayed in him.”— John 9:1-3 (BSB)