Final answer:
The correct answer to the question 'The Georgia Aquarium’s exhibits, containing some of the most exotic aquatic animals in the United States, differ greatly in size and diversity __________.' is option C: from those at the Chattanooga Aquarium.
Step-by-step explanation:
The proper phrase to use when comparing the exhibits of the Georgia Aquarium to another is 'differ from those at the Chattanooga Aquarium'.
This is the appropriate phrase to use when comparing two different things in English. Using 'differ from' correctly indicates that there is a variation or contrast between the Georgia Aquarium’s exhibits and those at the Chattanooga Aquarium. Option B is incorrect because 'to' is not conventionally used when expressing differences. Option D is also incorrect for the same reason, and option A (NO CHANGE) lacks the necessary comparison.