Which term refers to major rivers under pressure, such as the Nile and Yangtze?

• A. Hydrologic Cycle
• B. Freshwater Shortages
• C. Aquifers
• D. Highly Stressed River Systems

Answer: (D)

The main idea is recognizing a term used for large rivers that are under intense pressure from competing uses and pollution. The Nile and Yangtze illustrate this clearly: they support vast irrigation, hydropower, industry, and urban needs, while also facing pollution and ecological stress. The phrase Highly Stressed River Systems specifically describes major rivers that experience substantial water stress and environmental pressure, capturing both the heavy demand and the quality challenges these rivers face. If we think of the other options: the hydrologic cycle is the global movement of water, not a label for stressed rivers; freshwater shortages speak to scarcity in general rather than the specific condition of major rivers; aquifers are underground water sources. So the term that best fits rivers like the Nile and Yangtze is Highly Stressed River Systems.