Passage Summary: Counterfeiters are using new tech to copy money. One defense, microprinting, is hard to copy but requires a pro to spot. A more expensive option, color-changing ink, lets anyone see if a bill is fake. The author thinks we should pay more for the ink version.

Conclusion: The government should adopt color-changing ink for currency instead of microprinting, despite the higher cost.

Reasoning: While microprinting is difficult to photocopy, it requires experts to detect fakes; color-changing ink allows the general public to easily identify counterfeits because the ink reacts to light in a way photocopies cannot.

Analysis: To weaken this argument, we need to find a reason why the color-changing ink isn't the silver bullet the author thinks it is. The argument assumes that 'easy detection' by the public is the most important factor, but perhaps criminals have found ways to simulate the color-shifting effect or the ink is prone to wearing off, making real bills look fake. Look for an answer choice that introduces a significant drawback to the ink or suggests that microprinting is more effective than the author admits.