I assume that these are the options.
the first option, tariff, is a form of tax.
the second option, work ethic, is indeed something the workers can do to improve the economy so this is the correct answer
Osaka is a city and trade surplus would be more an effect than it cause for good economy
1. Great depression
2. new deal
3. prohibition
4. Manhattan project
5. rationing
6. rosie the riveter
7. pearl harbor
8. lend lease program
9. axis powers
10. island hopping
11. internment camps
12. D day
13. battle of midway
14. victory gardens
15. neutrality acts
16. fall of Berlin
17. allied powers
18. Hiroshima and Nagasaki