Question

Which one of the following Phanerozoic periods has the shortest duration of time?

• A. Cambrian
• B. Devonian
• C. Cretaceous
• D. Silurian

Hint:

Always remember: among Paleozoic periods, the Silurian is the shortest (~24 Myr). This type of question often tests relative duration.

Answer 1

The Correct Option is D

Step 1: Recall the Phanerozoic Eon divisions. The Phanerozoic Eon (541 Ma to present) is divided into Paleozoic, Mesozoic, and Cenozoic eras, each containing multiple periods.

Step 2: Approximate durations. - Cambrian: ~541–485 Ma → about 56 million years. - Devonian: ~419–359 Ma → about 60 million years. - Cretaceous: ~145–66 Ma → about 79 million years. - Silurian: ~443–419 Ma → about 24 million years.

Step 3: Compare durations. The Silurian Period is clearly the shortest, lasting only about 24 million years.

Final Answer: \[ \boxed{\text{Silurian}} \]