The sentence in which the adverb clause modifies an adjective is the second one - The veteran appeared proud as he saluted the flag.
The adjective here is <em>proud</em>, and the adverbial clause is <em>as he saluted the flag. </em>As you can see here, that clause is describing the adjective in more detail.
When did the veteran appear proud? - As he saluted the flag (it obviously modifies the word <em>proud</em>)
Answer:
The story probably takes place in Italy during the 18th or 19th century.
Explanation:
1. Therefore
2. All in All
3. However
4. In spite of
5. For example
6. Nevertheless
7. Simply because
8. In addition
9. For instance
10. For this reason
11. Further
12. Given These points
13. Along with
14. Indeed
15. That is
Bonus: Morever