Final answer:
Jesus stated that the sign made available to an evil and adulterous generation would be the 'sign of the prophet Jonah,' which symbolizes His death, burial, and resurrection, paralleling Jonah's experience in the fish.
Step-by-step explanation:
The question pertains to what Jesus said would be a sign for an evil adulterous generation. According to the Gospel of Matthew, Jesus referenced the Prophet Jonah as a sign to an evil and adulterous generation. In Matthew 12:39-40, Jesus states, 'An evil and adulterous generation seeketh after a sign; and there shall no sign be given to it, but the sign of the prophet Jonas: For as Jonas was three days and three nights in the whale's belly; so shall the Son of man be three days and three nights in the heart of the earth.'
This scriptural reference is to Jesus's own death, burial, and resurrection, which parallel Jonah's experience in the belly of the great fish, and which serve as a divine sign to those Jesus was addressing. The emphasis is on the generation's desire for a sign and the provision of a sign that points to Jesus's authority and mission as the Messiah.