Which of the earth-system scientist's roles is best illustrated by this paragraph? Emission testing is required by federal law in areas that have had problems meeting health-based air quality standards. Such areas typically include industrialized urban areas and large cities. Supporters of this practice argue that all citizens benefit because vehicles with malfunctioning pollution control systems are identified. They also cite government data showing average failure rates of 10%. Critics of the testing argue that those data are heavily influenced by older vehicles that fail 30% of the time, and vehicles less than 5 years old fail less than 1% of the time. A law has been placed on the ballot to stop testing for vehicles less than 5 years old.

A. Alerting the public of natural hazards
B. Use of earth resources
C. Health of the environment
D. Informing society

Scientist: cross-sections of stalactites—calcite formations deposited on cave ceilings by seeping water—can reveal annual variations in rainfall in particular areas over hundreds and thousands of years. we often found that when—according to these cross-sections—drought occurred in a particular area, it coincided with the collapse of an ancient society in that area. i hypothesize that drought reduced agricultural productivity in these areas, thereby leaving these societies without the resources needed to handle internal stresses and external threats. which of the following, if true, would most weaken the support for the scientist's hypothesis? a. many droughts indicated in the cross-sections of stalactites do not correspond with the collapse of a society in that area. b. information from the cross-sections of stalactites alone cannot reveal the level of agricultural output in an area at a particular time. c. most of the societies that collapsed during droughts did so when internal power struggles coincided with military raids from neighboring societies. d. most of the societies that collapsed during droughts maintained large stockpiles of food and water at the time of their collapse. e. information from stalactites also suggests that the collapse of some societies coincided with periods of abnormally high rainfall.