Explanation:

- Tia wanted a dog that was __________ than Larry’s dog. The sentence uses comparative language.

- Option 1: "smarty and strong" - "Smarty" is not a standard adjective form; it should be "smarter." This option is incorrect.

- Option 2: "smartest and strongest" - These are superlatives, which compare more than two items; not suitable here.

- Option 3: "smarter and stronger" - This option uses comparative adjectives correctly, suitable for comparing two items.

- Option 4: "smart and strong" - This option does not use comparative adjectives, so it doesn't show comparison.