How do I remove all but one color in Photoshop?

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Tags

1. #saturation
2. #selected
3. #picture
4. #color
5. #slide
6. #click
7. #image
8. #areas
9. #below
10. #background
11. #removing
12. #adjustments
13. #except
14. #button
15. #select
16. #layer