Which of the following statements about the Cambrian Explosion is true?

• A. It occurred after the Permian mass extinction.
• B. It was characterized by the extinction of most marine species.
• C. It was a period marked by a rapid diversification of animal life forms.
• D. It was the time when the first land plants appeared.

Answer: (C)

Verified step by step guidance

1. Understand the Cambrian Explosion: The Cambrian Explosion refers to a period approximately 541 million years ago during the Cambrian period, characterized by a rapid diversification of multicellular animal life forms in the fossil record.
2. Clarify the timeline: The Cambrian Explosion occurred long before the Permian mass extinction, which happened about 252 million years ago. Therefore, the statement 'It occurred after the Permian mass extinction' is incorrect.
3. Evaluate the extinction claim: The Cambrian Explosion is not associated with the extinction of most marine species. Instead, it is known for the emergence of many new marine species. Thus, the statement 'It was characterized by the extinction of most marine species' is incorrect.
4. Analyze the appearance of land plants: The first land plants appeared later, during the Ordovician period, not during the Cambrian Explosion. Therefore, the statement 'It was the time when the first land plants appeared' is incorrect.
5. Identify the correct statement: The Cambrian Explosion is best described as a period marked by a rapid diversification of animal life forms, which is the correct answer.