Question

During the 19th-century "Gold Rush" era, thousands of prospectors flooded into California, yet many failed to find significant amounts of gold and abandoned their claims. Records indicate that only a fraction of the gold present in the Sierra Nevada foothills was actually recovered during this period. However, modern geological surveys and amateur prospectors using advanced metal detectors still occasionally locate rich, untouched veins of gold in areas once deemed exhausted. This suggests that ______
Which choice most logically completes the text?
A) most gold prospectors in the 19th century were not using proper equipment.
B) the amount of gold originally present in California was overestimated.
C) there is still potential for discovering significant, undiscovered gold deposits.
D) modern technology has made 19th-century mining techniques irrelevant.

Answer 1

C

The passage notes that only a fraction of the gold was recovered and that modern surveys and detectors still uncover rich veins in supposedly exhausted areas, which most directly supports the conclusion that significant undiscovered gold deposits may still exist. Choices A, B, and D are either too strong or contradicted by the evidence.