Each sentence distinguishes the actor from any tool being used. Which sentence uses by for an instrument even though a person is named as its operator?
The orchard was inspected by a trained arborist, the agent.
The carpenter operated the electric drill, but the pilot hole was made by the drill, the stated instrument.✓Richtige Antwort
The wet print was lifted with broad tongs, the tool used by the conservator.
The abandoned nest was rebuilt by the parent birds, the agents.
Erklärung
The drill sentence conflicts with its own premise: the carpenter is the operator and the drill is the instrument, so the passive phrase requires with. By can introduce a nonhuman cause in another context, but under the stated roles it misclassifies the tool.