Free SAT Practice Question

Question 1 of 1
ID: SAT-RW-II-035
Section: SAT Reading & Writing (RW) – Information and Ideas
Topic: Command of Evidence – Textual
Difficulty level: Medium

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Some ancient Roman harbor structures have stood in seawater for two thousand years with remarkably few cracks, a durability modern concrete rarely matches. The materials scientist Priya Venkataraman proposes an explanation. Roman builders, she suggests, mixed their concrete with quicklime at high temperatures, a process that left small white lumps of lime, called lime clasts, scattered through the hardened material. When a crack later formed and seawater seeped in, Venkataraman argues, these clasts dissolved and then redeposited as fresh mineral that filled the crack and sealed it before it could spread.

Which finding, if true, would most directly support Venkataraman's explanation?

AUnder a microscope, Roman harbor concrete is found to contain far more lime clasts, evenly distributed, than concrete mixed at ordinary temperatures does. The bright specks turn up in sample after sample, scattered evenly throughout the hardened material wherever the mix was heated to a high enough temperature.

BSamples of the Roman concrete owe much of their strength to volcanic ash, which reacts slowly with seawater to form interlocking crystals throughout the material.

CIn aged samples, cracks that ran through a lime clast were later found refilled with newly formed mineral, while cracks in clast-free regions stayed open, and modern replicas made without lime clasts did not reseal.

DThe samples with the highest density of lime clasts developed the widest cracks, which continued to grow wherever a clast had dissolved and left a void.

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