Gause’s ‘Competitive Exclusion Principle’ states that -

The correct answer is Option (1) → Two closely related species competing for the same resources cannot co-exist indefinitely and the competitively inferior one will be eliminated eventually

Competition is a contest for the same limited resource. Gause’s principle says what happens when two similar species share one resource.

(1) Two closely related species competing for the same resources cannot co-exist indefinitely and the competitively inferior one will be eliminated eventually — Correct. This is the principle as stated. The weaker competitor is driven out.

(2) Two closely related species competing for the different resources cannot co-exist indefinitely and the competitively inferior one will be eliminated eventually — Incorrect. Species that use different resources do not compete for them, so neither is forced out.

(3) Two closely related species competing for the same resources can co-exist indefinitely and the competitively superior one will be eliminated eventually — Incorrect. It is the inferior species that is eliminated, and the two cannot co-exist indefinitely.

(4) Two closely related species competing for the different resources can co-exist indefinitely and the competitively superior one will be eliminated eventually — Incorrect. The superior species is not the one eliminated. Using different resources also means there is no competition.

Note: A similar question was also asked in CUET (UG) 2025 on 02-06-2025 (Slot 2), on 30-05-2025 (Slot 1) and on 23-05-2025 (Slot 2).

NCERT Extract:
Population Interactions –