Question

question: which of the eras in recent geological history is the oldest? answer options: select one of four phanerozoic paleozoic cenozoic mesozoic

Explanation:

To determine the oldest era among the given options, we analyze the geological time scale. The Phanerozoic Eon is divided into three eras: Paleozoic, Mesozoic, and Cenozoic. The Paleozoic Era is the earliest of these three eras within the Phanerozoic, occurring before the Mesozoic and Cenozoic. The Phanerozoic is an eon, not an era in the same sub - division as the other three options (which are eras within the Phanerozoic). So among the era options (Paleozoic, Mesozoic, Cenozoic), Paleozoic is the oldest.

Answer:

B. Paleozoic