What did they encounter when they reached the river, and why was the time of year important?

• A. Steel cable used to chart river fluctuations; important because river levels change seasonally.
• B. A bridge was found and it made crossing easy.
• C. A rope and buoy were used; season didn't matter.
• D. A motor boat was available; season was important because it was dry.

Answer: (A)

Rivers change with the seasons, and people study those changes to decide when and how it’s safe to cross. Encountering a steel cable used to chart river fluctuations shows someone was measuring how the river level varied over time, not just looking for a path. The time of year matters because snowmelt and seasonal rains can raise water levels, making crossings riskier, while drier seasons may lower the water and change crossing strategies. The other ideas imply different crossing aids or no seasonal effect, which doesn’t fit the evidence of a measurement setup tied to seasonal water changes.