"Observation is the test of scientific truth. So far, observations of the earth's temperature has not revealed signs of a human-induced global warming." -- George C. Marshall Institute, 1997 Which of the following statements best reflects and agrees with the quote? A Scientists disagreed on whether human activity had a significant impact on Earth's temperature. B Studies have proven that industrialization has had no measurable impact on the environment. C Recent laws were successful in limiting the long-term effects of industrialization on the Earth. D Researchers have not found evidence humans cause or control Earth's temperature changes.