Excerpt from Transportation and our Nation's Energy Consumption Robert J. Shapiro, Conserving Energy and Preserving the Environment: The Role of Public Transportation 3 Public transportation needs to be an essential element in sound national energy and environmental policies. Potential threats to the supply and price of foreign oil as a result of terrorism, conflicts in the Middle East, and OPEC decisions underscore the need for a public transportation strategy that reduces our nation's dependence on imported oil. Likewise, ongoing efforts to reduce harmful emissions from our air can be more effective when they include ways to increase use of public transportation. The last sentence in section 3 increases coherence with its effective use of A) a transition. B) documentation. C) an abbreviation. D) parallel construction.