Its central role in field-work because it yields the most reliable evidence for human activities in the past and changes in those activities from period to period.

excavation

Explanation:

Excavation retains its central role in field-work because it yields the most reliable evidence for human activities in the past and changes in those activities from period to period.

In archeology, excavation is the procedure by which archaeologists define, retrieve, and record cultural and biological remains found in the ground. It is an important archaeological tool for understanding the processes of the human past. Past activities leave traces in the form of house foundations, graves, artifacts, bones, seeds, and numerous other traces which are helpful in studying the way of life of the people who lived in that era. Excavation helps uncover this remains.