[ 467 ] Economics GED ® TEST SOCIAL STUDIES FLASH REVIEW _____________ • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 5 0 5 0 5 0 0 5 1 7 8 9 7 8 9 0 0 1 9 9 9 9 9 9 0 0 0 1 1 1 1 1 1 2 2 2 The following chart depicts crude oil prices between 1970 and 2012. Crude Oil Prices 2011 Revolution in Libya 2008 Start of worldwide recession 1979 Iranian Revolution 1980 Start of Iran-Iraq War 2003 US invasion of Iraq; start of Iraq War 1998–1999 OPEC cuts 4.2 million barrels 1990 Gulf War 2001 9/11 terrorist attacks 1973 OPEC oil embargo 1997 Start of Asian Financial Crisis; 10% OPEC quota increase $90 $80 $70 $60 $50 $40 $30 $20 $10 $0 US$/barrel Source of Data: Vehicle Technologies Office; US Department of Energy (http://www1.eere .energy.gov/vehiclesandfuels/facts/m/2012_fotw742.html); WTRG Economics (http://www.wtrg .com/oil_graphs/oilprice1970.gif). Since 1970, the price of oil has fluctuated. According to the chart, what is the most common cause of increases in oil prices? a. the manipulations of oil speculators b. the control of the market by OPEC c. conflict in the Arab World and Middle East d. shocks to the world economy