Which method can be employed to remove a very large stump or rock?

The most effective method for removing a very large stump or rock among the choices provided is to excavate deeper than the stump. This approach allows for a clearer understanding of the size and root system of the stump, facilitating better access and control when attempting to dislodge it.

By digging deeper, the operator can sever roots that may be anchoring the stump in place, enabling a more effective extraction process. Additionally, this method ensures that the surrounding soil and material can be repositioned easily around the stump, reducing the amount of labor and time required for complete removal.

Other methods might seem practical but do not provide the same effectiveness in terms of overall clearance and safety. For example, merely adding dirt to the deepest parts of the hole would not provide the necessary leverage or structural support to remove the stump; it would likely have the opposite effect. Using a chainsaw to cut the stump may only work if the stump is accessible and not too large, and doesn't address the roots, which may still hold it in place. Attaching it to a vehicle can be risky, especially if the stump or rock is not adequately freed from the ground, which could lead to equipment damage or safety hazards.