Multiple choice Competitions for water, minerals, light and space is most severe between two closely related species occupying the same niche closely related species occupying the different niche unrelated species occupying the same niche species occupying different overlapping Reveal answer Fill a bubble to check yourself A Correct answer Explanation Competition is most intense between closely related species occupying the same niche (identical resource needs). This is the competitive exclusion principle - two species competing for identical resources cannot stably coexist.