Final answer:
Dendrochronology is the study of tree rings to determine past climates and date archaeological remains. Scientists analyze the secondary xylem in their research, which allows them to piece together long chronological records and validate carbon dating.
Step-by-step explanation:
Dendrochronology is the science that deals with determining past climates and archaeological dating by examining the features of tree rings. When scientists study tree rings for dendrochronology, they specifically look at the secondary xylem, which is the correct answer to the multiple-choice question provided, option b. As trees grow, they develop annual rings made up of earlywood and latewood, which reflect the environmental conditions of each growing season.
These annual rings can be read much like a natural archive, offering insights into past weather patterns, thereby contributing to our understanding of historical climate. Not only can dendrochronology provide data on environmental changes, but it also aids in the dating of wooden structures and artifacts, such as those at the Pueblo Bonita site in Chaco Canyon.
Dendrochronologists piece together long chronological records by matching overlapping tree ring patterns from multiple trees, creating an extended chronology that goes beyond the life of any single tree. This technique plays a crucial role in validating methods like carbon dating and contributes to the broader field of paleoclimatology and historical research.