Final answer:
The saying 'As rich as...' can be completed with any of the options a. Midas, b. Croesus, c. Tantalus, or d. Plutus, all of which symbolize extreme wealth and prosperity.
Step-by-step explanation:
The saying 'As rich as...' can be completed with any of the options a. Midas, b. Croesus, c. Tantalus, or d. Plutus. All of these options refer to characters from mythology or history who were known for their wealth and riches.
For example, 'As rich as Midas' refers to King Midas from Greek mythology, who was granted the power to turn everything he touched into gold. This saying indicates extreme wealth and abundance.
Similarly, Croesus was a wealthy king from ancient Lydia, known for his vast riches. Tantalus and Plutus were also associated with wealth and prosperity in different mythological contexts.