Choices: (I). O3; (II). O2; (III). oil; (IV). pan; (V). h2o; (VI). CO2; (VII). DNA; (VIII). DDT;

Fact 1: Ozone depletion results in higher levels of UV radiation reaching Earth. Fact 2: Ozone is represented chemically as O3. Given the two facts above, the depletion of what results in higher levels of UV radiation reaching Earth?
Answer:
(I).