01 What may a sudden colour change in a soil layer indicate?
Answer and explanation
Correct answer: A. A new layer or different activity
Explanation: A change in soil colour can mark a boundary between deposits with different materials or origins. It may reflect ash, a fill, erosion, construction, burning, or another human activity, but colour must be checked with texture and finds. Therefore option A is best; it does not by itself prove modernization, object disappearance, or river drying.