Evaluate the two proposed answers. Which are supported? I. Sinkhole in limestone terrain — the process primarily responsible: Deposition of glacial debris. II. Alluvial fan at a mountain front — the process primarily responsible: Deposition as stream gradient falls.
Correct answer: A
I is incorrect: Sinkhole in limestone terrain → Solution and collapse. Dissolution enlarges underground openings that may collapse. II is correct: Alluvial fan at a mountain front → Deposition as stream gradient falls. A stream loses carrying capacity on entering a flatter area.