What is Mutualism?

• A. A relationship in which both species benefit (symbiotic relationship)
• B. A relationship where one organism benefits and the other is harmed
• C. A relationship where both species are unaffected
• D. A relationship where one species dominates the other

Answer: (A)

Mutualism is a kind of symbiotic relationship in which both species benefit from their interaction. This is the best answer because it describes a cooperative association where each participant gains a fitness advantage, such as flowers getting pollinated by bees and bees obtaining nectar, or gut bacteria helping with digestion while receiving a nutrient-rich environment. This contrasts with relationships where one organism is harmed (parasitism) or where the other is unaffected (commensalism). Mutualism can be obligate, meaning both need the other to survive, or facultative, where they can live apart but thrive better together.