Correct option is B. Ozone in Troposphere is not good for breathing
Ozone present in the stratosphere, acts as a
protection from U.V. light. Without this protective
shield, all life would be more susceptible to
cancer, impaired immunity and other health issues.
Whereas the ozone present in the troposphere,
which is close to earth surface, can damage our
lungs. Hence it is not good for breathing.