Choose the correct option:

Question

Accepted Answer

The longest span on the geological scale is era.

**Explanation:**

Option 2 is correct because the geological timescale is hierarchically organized, and eras represent a larger division of time than epochs, periods, or any other unit listed in the incorrect options. The general order, from largest to smallest, is:

*   **Eon:** The largest division of geological time.
*   **Era:** Eons are divided into eras.
*   **Period:** Eras are divided into periods.
*   **Epoch:** Periods are divided into epochs.
*   **Age:** Epochs are divided into ages.

Therefore, an era encompasses a longer duration than a period, epoch, or age.

**Why the other options are incorrect:**

*   **Option 1: The longest span on the geological scale is epoch.** This is incorrect because epochs are the shortest of the time spans listed. Epochs are subdivisions of periods, which are themselves subdivisions of eras and eons.

*   **Option 3: Periods are divided into eras.** This is incorrect because the relationship is reversed. Eras are divided into periods, not the other way around.

*   **Option 4: Epochs are further divided into periods.** This is incorrect because epochs are subdivisions *of* periods. Periods are not created by dividing epochs; rather, epochs are created by dividing periods.