Question

read the passage and answer the following question(s).
human activities and earths atmosphere
evidence from scientific studies supports the claim that human
activities are contributing to the increasing average global surface
lempcrature on earth as observed for the past 100 years. the
concentration of greenhouse gases in earths atmosphere have
increased during this time and are thought to be the major cause for
changes in global climate. graph 1 represents the relative
contribution of human activities that are likely causing global climate
change. graph 2 represents the relative amounts of various
greenhouse gases in the atmosphere.
graph 1: contribution of human greenhouse gases in atmosphere
graph 2: relative amounts of
a group of environmental scientists wants to make a plan that will reduce
human impact on average global temperature. which of the following plans
is most likely to have the greatest effect on global temperature?
o a. a plan to reduce chlorofluorocarbons in the atmosphere by 20%.
? b. a plan to reduce carbon dioxide in the atmosphere by 20%.
o c. a plan to reduce methane in the atmosphere by 20%.
o d. a plan to reduce nitrous oxide in the atmosphere by 20%.

Explanation:

Looking at Graph 2 "Relative Amounts of Greenhouse Gases in Atmosphere", carbon dioxide has the highest proportion (72.5%) among the greenhouse gases shown. To have the greatest effect on global temperature (since carbon dioxide is a major greenhouse gas contributing to the greenhouse - effect and thus global temperature changes as per the passage's context about human activities and Earth's atmosphere), reducing the most abundant greenhouse gas (carbon dioxide) would be most impactful.

Answer:

B. A plan to reduce carbon dioxide in the atmosphere by 20%