1. PART A: Which statement best expresses the central
idea of the text?
O A Carbon dioxide is a naturally produced gas that is
necessary for our atmosphere to trap heat and
support life on Earth.
LOB While carbon dioxide is a greenhouse gas and
contributes to global warming, burning fossil fuels is
necessary to power modern technology.
O C Humans have altered the surface of the Earth
through deforestation and development, and it is no
longer able to adequately reflect heat.
• D Humans are responsible for the rising level of
greenhouse gases in the atmosphere, and the
resulting warming of the Earth.