Which of the following best explains the presence of vestigial structures in organisms?

• A. They are adaptations that provide a significant survival advantage in the current environment.
• B. They are structures that have always been nonfunctional and serve no evolutionary purpose.
• C. They are inherited from ancestors and have lost their original function due to evolutionary changes.
• D. They are newly evolved structures that have not yet developed a function.

Answer: (C)

Verified step by step guidance

1. Understand the concept of vestigial structures: Vestigial structures are anatomical features or behaviors that were functional in an organism's ancestors but have lost their original function due to evolutionary changes. They are evidence of an organism's evolutionary history.
2. Analyze the options provided: Carefully read each option and determine whether it aligns with the definition and characteristics of vestigial structures.
3. Option 1: 'They are adaptations that provide a significant survival advantage in the current environment.' This is incorrect because vestigial structures do not provide a survival advantage; they are remnants of ancestral traits.
4. Option 2: 'They are structures that have always been nonfunctional and serve no evolutionary purpose.' This is incorrect because vestigial structures were functional in ancestors and are evidence of evolutionary processes, even if they no longer serve a purpose.
5. Option 3: 'They are inherited from ancestors and have lost their original function due to evolutionary changes.' This is correct because it accurately describes vestigial structures as inherited traits that have lost their original function over time. Option 4: 'They are newly evolved structures that have not yet developed a function.' This is incorrect because vestigial structures are not newly evolved; they are remnants of ancestral traits.