Although fiber-optic telephone cable

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TopicsMost Supported

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Stimulus

Although fiber-optic telephone cable is more expensive to manufacture than copper telephone cable, a telephone network using fiber-optic cable is less expensive overall than a telephone network using copper cable. This is because copper cable requires frequent amplification of complex electrical signals to carry them for long distances, whereas cable can travel much farther before amplification is needed.

What this question is testing

Most Supported

Your task

Break the argument into its conclusion and evidence, then do exactly what the question stem asks with that structure.

Common trap

Answers that sound relevant to the topic but don't connect to the argument's actual reasoning.

Winning move

Predict what a right answer must do, then test each choice against the conclusion-evidence gap.

Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.

The question

The above statements, if true, most strongly support which one of

Answer choices

Too Speculative5% picked this
The material from which fiber-optic cable is manufactured is more expensive than the copper from which
This answer is attempting to explain why fiber-optic is more expensive to manufacture than is copper. But it might have nothing to do with more expensive materials. Maybe it's a more laborious manufacturing process so it's pricier because it takes longer to make. We shouldn't be speculating the backstory of the facts we're reading. We want to find an answer that's more or less provably true based on the facts we do possess.
5%
Out of Scope: # of transmissions1% picked this
The increase in the number of transmissions of complex signals through telephone cables is straining those telephone networks
We don't have any information about any current increase in the number of transmissions, nor do we get any sense that any network is straining.
1%
Out of Scope: carry more signals4% picked this
Fiber-optic cable can carry many more signals simultaneously than copper
Nothing in the passage gets into comparing how many signals each type of network can carry at any given time.
4%
Out of Scope1% picked this
Signals transmitted through fiber-optic cable travel at the same speed as signals transmitted
Out of Scope: speed of transmission Too Strong: same The passage never compared the speed at which signals travel, so we have no way to derive the extreme claim that both signals travel as the same speed.
1%
Correct90% picked this
The cost associated with frequent amplification of signals traveling through copper cable exceeds the extra manufacturing
Why this is right
We were told that copper is cheaper than fiber-optic to produce, but a network based on copper cable is more expensive overall, because on the copper network you have to frequently amplify the signal. So that implies that the extra money you have to spend on amplification outweighs the money you saved on the cheaper cable.
Skill tested: Most Supported · how this choice captures the argument's function is the move to repeat next time.
90%

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