In the following question, out of the given four alternatives, select the one which is opposite in meaning to the given word.
Hummock

Hummock refers to a small hill, knoll, or mound of earth/ice (an elevated land feature).
Ditch: Means a narrow channel dug in the ground, typically for drainage (a depression/low feature), making it the exact opposite in meaning.

Ridge, Hill, Upland: These are all related to elevated ground features and act more like synonyms.