A geologist claims that a particular river delta is shrinking because upstream dams trap the sediment that historically reached and replenished it, rather than because of rising sea levels.
Which finding, if true, would most strongly support the geologist's claim?
- A
Some dams generate hydroelectric power.
- B
Many river deltas worldwide are losing area.
- Ccheck_circle
Sediment volumes reaching the delta dropped by more than 80 percent after upstream dams were built, even though local sea level has risen only modestly during the same period.
- D
Rising sea levels are a global concern.
Explanation
A directly compares sediment loss (large) to sea-level rise (modest), supporting the dam-driven mechanism. B, C, and D are general or tangential.