[Campbell Biology P.582] According to the provided text, which of the following statements i... | Practice Question

According to the provided text, which of the following statements is true regarding Earth's geologic history?

  • A: The Mesozoic era is characterized by the abundance of reptilian fossils, including dinosaurs.
  • B: The oldest fossils of eukaryotic cells appeared about 3.5 billion years ago.
  • C: The Cambrian explosion, a sudden increase in animal diversity, occurred approximately 140 million years ago.
  • D: Humans appeared approximately 9 minutes ago on a 1-hour geological timer scale.

Explanation

The text explicitly states: 'The Mesozoic era is sometimes called the "age of reptiles" because of its abundance of reptilian fossils, including those of dinosaurs.' This directly confirms option A. Other options contain inaccuracies regarding dates or interpretations of the timeline.