The correct answer would be option C: "have been handed down through many generations". The speaker gave many examples in the excerpt of how his grandfather's grandparents had used the Balek scales such as: "their grubby hands holding their little baskets of mushrooms", to show that the scales are a family relic and where passed down until they reached the speaker.
The speaker does not say or imply that the scales have never moved, nor that those that use them feel frightened or intimidated. He also never says anything that implies that the scales do not work, therefore options A, B and D are incorrect.