The correct answer is C.
Excavation in archeology is the controlled exploration of what lies under the surface. It is usually carried out in an ordered way in gridded trenches with a shovel and trowel. It is often slow and tedious work which involves digging down a centimeter at a time, but can be back breaking and difficult toil, sometimes shoveling through meters of densely packed soil. Either way, the purpose is basically the same, to uncover and reveal the type of human activities that took place at particular site over time.
