Explanation
There are 22 languages present in the Eighth Schedule.
Here is the list of these 22 languages:
1. Assamese
2. Bengali
3. Bodo
4. Dogri
5. Gujarati
6. Hindi
7. Kannada
8. Kashmiri
9. Konkani
10. Maithili
11. Malayalam
12. Manipuri (also referred to as Meitei or Meithei)
13. Marathi
14. Nepali
15. Odia (formerly spelled as Oriya)
16. Punjabi
17. Sanskrit
18. Santali
19. Sindhi
20. Tamil
21. Telugu
22. Urdu
So, the correct option is D: 22.