Final answer:
The second smallest division of geologic time is the epoch, smaller than a period and larger than an age.The second smallest division of time is the Epoch. Geologic time is divided into eons, which are subdivided into eras. Eras are further divided into periods, and periods are divided into epochs. Therefore, the epoch is the second smallest division of time on the geologic time scale
Step-by-step explanation:
The second smallest division of time in the geologic time scale is the epoch. In hierarchical order, an eon is the largest division and is subdivided into eras. Within eras, we find periods, and periods are further divided into epochs, and finally, epochs into ages. Based on this categorization, an epoch is smaller than a period, making option D. Epoch the correct answer to the question.