Well there could be problems with food, and if there is a sickness, or a desater, like flooding around you could not move on. Also the population can reduce food, and water.
He realized that because of his conduct of the War in Vietnam he could not win the Democratic Nomination
After the Tet offensive the American voters became disillusioned with the conduct of war in Vietnam and how it could be ended
It is definetly c. I think the question is should be conservation in America.
Because conservation generally talks about biodiversity,Environmental and natural resources
July 28, 1914 – November 11, 1918