Questions: 3. Which statement concerning the ozone layer is TRUE? The ozone layer provides a protective barrier from the Sun. The ozone layer has holes in it above the North Pole. The ozone layer is one of the five layers of the atmosphere. The ozone layer provides oxygen for life on Earth.

The answer is the first one: The ozone layer provides a protective barrier from the Sun.

Explanation for each option:

1. The ozone layer provides a protective barrier from the Sun.

   • This statement is true. The ozone layer absorbs the majority of the Sun's harmful ultraviolet (UV) radiation, particularly UV-B and UV-C rays, which can cause skin cancer and cataracts, and can also harm marine life and ecosystems.

2. The ozone layer has holes in it above the North Pole.

   • This statement is incorrect. While there is significant thinning of the ozone layer, commonly referred to as the "ozone hole," it is primarily observed over the Antarctic region (South Pole) rather than the North Pole.

3. The ozone layer is one of the five layers of the atmosphere.

   • This statement is incorrect. The ozone layer is not a separate layer of the atmosphere but a region within the stratosphere, which is one of the five main layers of the Earth's atmosphere (troposphere, stratosphere, mesosphere, thermosphere, and exosphere).

4. The ozone layer provides oxygen for life on Earth.

   • This statement is incorrect. The ozone layer does not provide oxygen for life on Earth. The oxygen we breathe comes from the troposphere, the lowest layer of the atmosphere. The ozone layer's primary function is to absorb and protect life from harmful UV radiation.

Summary: The correct statement is that the ozone layer provides a protective barrier from the Sun by absorbing harmful ultraviolet radiation.