What percentage of air is oxygen?

Multiple Choice Questions on Nature’s Treasures – Class 6 Science Quick Revision
MCQs are a great way to revise important topics from Class 6 Science Chapter 11. Covering areas like conservation, natural habitats and human impact, these questions help students recall key facts quickly. Each answer is backed with an explanation to ensure thorough understanding before exams.

Ans.: (B)
The percentage of oxygen in the air is 21%.