Concept:The in-situ breakdown of rocks by physical or chemical processes is called weathering.Explanation:The question states that rocks are disintegrated "in situ," meaning they break down without being transported away.Erosion involves the removal of rock particles from their original location.Transportation is the movement of weathered materials from one place to another.Deposition is the laying down of transported sediments.Only weathering describes the disintegration of rocks in place.Hence, the correct answer is weathering.Answer:D. weathering