A symbiotic relationship where one organism benefits and one is harmed is known as:

• A. Mutualism
• B. Parasitism
• C. Amensalism
• D. Commensalism

Answer: (B)

Verified step by step guidance

1. Step 1: Begin by understanding the concept of symbiotic relationships. Symbiosis refers to a close and long-term biological interaction between two different organisms.
2. Step 2: Review the definitions of the given options: Mutualism (both organisms benefit), Parasitism (one organism benefits while the other is harmed), Amensalism (one organism is harmed while the other is unaffected), and Commensalism (one organism benefits while the other is unaffected).
3. Step 3: Focus on the key aspect of the question: 'one organism benefits and one is harmed.' This matches the definition of parasitism.
4. Step 4: Recall examples of parasitism, such as a tapeworm in a human host, where the tapeworm benefits by absorbing nutrients while the host is harmed.
5. Step 5: Conclude that the correct answer is Parasitism, as it aligns with the description provided in the question.