Which of the following is used to determine whether two populations belong to the same species?

• A. Similarity in habitat preference
• B. Ability to interbreed and produce fertile offspring
• C. Geographic proximity
• D. Presence of similar physical traits

Answer: (B)

Verified step by step guidance

1. Understand the concept of a biological species: A species is defined as a group of organisms that can interbreed and produce fertile offspring under natural conditions.
2. Evaluate the options provided in the question: Consider how each option relates to the biological species concept.
3. Option 1: 'Similarity in habitat preference' - While habitat preference can influence interactions between populations, it does not directly determine whether they are the same species.
4. Option 2: 'Ability to interbreed and produce fertile offspring' - This aligns directly with the biological species concept, as it is the primary criterion for defining species.
5. Option 3: 'Geographic proximity' and Option 4: 'Presence of similar physical traits' - These factors may contribute to the likelihood of interbreeding but are not definitive criteria for species classification. Focus on the ability to interbreed and produce fertile offspring as the correct answer.