Read the passage below carefully, and then choose the best answer

A. stand up

B. sit up

C. get up

D. spring up

A. cover

B. provide

C. make up for

D. compensate for

A. plans

B. orders

C. ways

D. structures

A. guarantee

B. shortage

C. population

D. habitat

A. necessary

B. major

C. fresh

D. aquatic

A. when natural-resource shortages increase in the features of gradually increasing demands from a rising human population

B. when a natural resource crosses political borders

C. when freedom could destroy the resource

D. when eroded soil and silt cloud affect many organisms

A. a river

B. topsoil

C. erosion

D. a forest

A. Argument often surrounds how a source should be used, or allocated, and for whom.

B. A river may provide water for agricultural irrigation, habitat for fish, and water-generated electricity for a factory.

C. Conservation methods are incidental to care for the river for future use.

D. Farmers, fishers, and industry leaders vie for open access to this river.

A. Conflicts improve when a natural resource crosses political borders.

B. The source of a main river may be located in the country through which the river flows than a different country.

C. There is assurance that the river source will be confined to provide accommodation for resource needs downstream.

D. The way where one ordinary source is managed has a direct effect upon other ordinary sources.

A. Natural-resource shortages

B. Agricultural irrigation

C. The headwaters of a major river

D. Conservation conflicts