Final answer:
The correct statement regarding secondary-school experiences in other countries is that C) 'School uniforms are common in many countries.' This reflects the widespread adoption of school uniforms in educational systems around the world.
Step-by-step explanation:
The statement about secondary school experiences in other countries that is true is: C) School uniforms are common in many countries.
This is accurate because, in many parts of the world, school uniforms are part of the educational culture and are required for students. This includes countries in Europe, Asia, Africa, and the Americas. Secondary education being mandatory is also not unique to the United States, as many countries require children to receive education up to a certain age.
Vocational education is also offered in numerous nations as an alternative or supplement to traditional academic courses. Lastly, school days' length varies from country to country, and students in some countries, such as South Korea, spend more days in school annually compared to U.S. students.