1. As the ozone layer gets thinner, the protective filter activity of the atmosphere is progressively reduced. Consequently, the people and the environment are exposed to higher levels of UV radiation, especially UVB. Exposure to UVB radiation is linked with increased risk of skin cancer and cataracts, as well as damage to plants and marine ecosystems.

What is the key structure of this text?




a.
descriptive


b.
sequence


c.
comparison - contrast


d.
cause - effect