Answer:
Symbiotic relationships (Ans. A)
Explanation:
Mutualism, commensalism, and parasitism are the three types of symbiotic relationship, where biological interaction occur between two organisms.
Mutualism: In this relationship both individual benefits.
Commenslism: In this relationship one organism is benefited and other is not harmed.
Parasitism: In this relationship, one organism is benefited and other is harmed.
