Analogy – choose the most appropriate pair: “Mountain” is related to “Hill” in the same way that “River” is related to which of the following?

Introduction / Context:
Analogy questions test recognition of a precise relationship between two words and the ability to transfer that relationship to a new pair. Here, “Mountain : Hill” indicates a category-and-degree relationship (larger-to-smaller natural landforms). We must find the hydrological pair with the same degree shift.

Given Data / Assumptions:

• First pair: Mountain compared with Hill (both landforms; a mountain is a larger or loftier form of a hill).
• Target domain: Fluvial or waterbody terms comparable to “River.”
• Options include several types of water features; only one should mirror the larger-to-smaller, same-kind relation.

Concept / Approach:
The governing relationship is “same kind, different magnitude.” A mountain and a hill are both elevated landforms; one is the larger, the other the smaller. By parallel reasoning, a river and a stream are both flowing watercourses; a river is the larger form, a stream the smaller. Therefore, River : Stream matches Mountain : Hill.

Step-by-Step Solution:

Verification / Alternative check:
Consider typical hierarchies: brook/creek/stream → river; knoll/hill → mountain. The direction and kind match in each hierarchy, confirming the choice.

Why Other Options Are Wrong:

• Canal, Reservoir, Tank: These are artificial water features, not natural smaller versions of a river.
• Lake: A standing waterbody (lentic), not a flowing watercourse like a river (lotic).

Common Pitfalls:
Choosing a word from a different subcategory (standing water vs. flowing water) or picking a man-made feature. Always preserve both “kind” and “degree.”

Final Answer:
Stream