Which of the following best describes the composition of ozone in the stratosphere above the Earth?

• A. Molecules containing three oxygen atoms (O_3)
• B. Molecules containing one oxygen atom and one nitrogen atom (NO)
• C. Atoms of oxygen (O)
• D. Molecules containing two oxygen atoms (O_2)

Answer: (A)

Verified step by step guidance

1. Understand that ozone is a specific molecule composed of oxygen atoms. It is important to distinguish between atoms and molecules in this context.
2. Recall that an oxygen atom is represented as O, while oxygen molecules commonly exist as O_2, meaning two oxygen atoms bonded together.
3. Recognize that ozone is a molecule made up of three oxygen atoms bonded together, which is represented as O_3.
4. Note that molecules containing one oxygen atom and one nitrogen atom (NO) are nitrogen oxides, not ozone.
5. Conclude that the composition of ozone in the stratosphere is best described as molecules containing three oxygen atoms (O_3).