The author refers to the construction of the aqueducts as the most remarkable achievement anywhere in the world because:
B. Aqueducts supplied water from great distances away, through mountains and valleys, for public drinking fountains and bathhouses.
The author highlights the extensive and impressive nature of the aqueducts' construction. The aqueducts brought water from faraway sources, overcoming geographical obstacles such as mountains and valleys. This water supply was not only used for essential purposes like public drinking fountains but also for luxurious amenities such as bathhouses. The scale and complexity of the aqueducts' construction, along with their extensive reach and the various purposes they served, contribute to their recognition as a remarkable achievement in the world.
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