The correct answer is B. Study information related to the Cenozoic era
Step-by-step explanation:
The purpose of a geologic time scale is to organize chronologically events of Earth's History, by diving time into eras, periods, ages, etc. In the case of the Eocene period, this occurred 34 million years ago; therefore, this period belongs to the Cenozoic era that covers events that occurred 65 Million Years Ago to Today as it is shown in the geological time scale.
In this context, to determine the era the Eocene belongs to it is important to study information related to the Cenozoic era especially the period of time this covers because through this you cannot know the Eocene belongs to the Cenozoic.