Which option correctly describes Stratigraphy?

• A. The study of the chemical properties of minerals.
• B. The analysis of Earth's sediment layers (strata) to estimate the age of fossils.
• C. The examination of animal behavior patterns.
• D. The analysis of tectonic plate movements.

Answer: (B)

Stratigraphy focuses on the order and position of rock and sediment layers and what those layers reveal about time. By examining how layers accumulate, which fossils they contain, and how they correlate across different places, scientists can determine the relative ages of rocks and the fossils within them—typically, younger layers sit above older ones, and fossils in those layers help establish a time framework. Fossils acting as clues across regions allow researchers to connect the same time period even when the rocks are far apart. This is different from looking at chemical properties, studying animal behavior, or tracking how tectonic plates move. So describing stratigraphy as the analysis of sediment layers to estimate the age of fossils captures the core idea.