The logical relationship between the two sentences is one of addition, as the second sentence provides an extra benefit or outcome of the campaigns mentioned in the first. The first sentence notes that anti-tuberculosis campaigns emphasized fresh air and sunlight due to limited options and some observed help, while the second adds that they 'also produced detailed municipal records' useful for later research on social factors in disease. This is supported by the word 'also,' which explicitly indicates something supplementary, building in the same direction without contrast or causation. Choice A, 'Conversely,' incorrectly signals opposition, but the records are a positive extension, not a reversal; Choice D, 'Still,' implies persistence despite difficulty, which doesn't fit the additive flow. In transition questions, look for subtle markers like 'partly because' in the first sentence, which can set up additional points rather than a single cause-effect chain.

The logical relationship between the two sentences is one of contrast, as the second sentence presents evidence that challenges or limits the initial assumption about restoring keystone predators. The first sentence describes the assumption that a keystone predator can rebuild the entire food web by suppressing mid-level consumers, while the second sentence uses 'long-term monitoring' to show that this only produces 'modest changes' when habitat is reduced, indicating the assumption doesn't fully hold. Key phrases like 'once assumed' set up an expectation that is countered by 'shows that... suggesting that top-down control depends on intact physical conditions.' Choice A, 'Consequently,' incorrectly signals a cause-effect relationship, as the monitoring results are not a direct outcome but a contradiction; similarly, Choice C, 'Moreover,' suggests addition, but the second sentence opposes rather than builds on the first. In transition questions, always identify the core relationship first—does the second sentence agree with, contradict, explain a result of, or add to the first?

The logical relationship between the two sentences is one of contrast, as the second sentence points out a drawback to the benefit mentioned in the first. The first sentence explains how adding carbon 'can dramatically increase hardness' by distorting the lattice, while the second contrasts this with 'also makes high-carbon steel more brittle,' leading to the need for balance. This opposition is clear in 'the same microstructural mechanism,' which ties the positive and negative effects together in tension. Choice A, 'Therefore,' incorrectly suggests a pure consequence without the downside; Choice B, 'Moreover,' implies addition of another positive, but this is a counterbalancing negative. In transition questions, watch for words like 'since' explaining a benefit in the first sentence, which often leads to a contrasting limitation in the second.

The logical relationship between the two sentences is one of cause-effect or illustration of consequence, as the second sentence provides a specific example of how averages can mislead. The first sentence warns that global averages 'can obscure regional extremes' due to varying spatial patterns, while the second demonstrates this with 'two decades... may still differ sharply in impacts if one... concentrates heat over major crop-growing regions,' showing the practical outcome. This is supported by 'because the same mean value can result from many different spatial patterns,' directly leading to the differing impacts described. Choice C, 'However,' incorrectly implies contrast, but the second builds on and exemplifies the first; Choice B, 'Similarly,' suggests parallelism without the causal link. In transition questions, always identify the core relationship first—does sentence 2 agree with, contradict, explain a result of, or add to sentence 1?

The relationship is concession or qualification—despite the dating method's reliability under ideal conditions (first sentence), it can fail under certain circumstances (second sentence). The first sentence includes the assumption "assuming the system remained closed," and the second shows what happens when this assumption is violated. Choice C "Nonetheless" correctly signals this "the method works, but can fail if conditions aren't met" relationship. Choice B "Thus" would incorrectly suggest the misleading age is a logical consequence rather than a problematic exception. Scientific method descriptions often include this pattern: technique works IF conditions are met, BUT fails when they're not.

The relationship is cause-and-effect—the algorithmic amplification described in the first sentence leads to the polarization described in the second. The first sentence explains the mechanism (algorithms amplify emotional content), and the second shows the consequence (increased polarization). Choice A "Accordingly" correctly signals this logical consequence. Choice B "However" would incorrectly suggest the polarization contradicts the amplification pattern, when it's actually a direct result of it. Social media analyses often follow this cause-effect pattern: platform design feature → societal consequence.

The logical relationship here is cause-and-effect, where the adaptations described in the first sentence lead to vulnerability described in the second. The first sentence explains how birds adapt to cities by using buildings and human food waste, while the second sentence shows how these same adaptations become problematic when trash is reduced—creating a direct consequence. Choice A "Consequently" correctly signals this cause-effect relationship, showing that the vulnerability is a result of the adaptations. Choice B "However" would incorrectly suggest contrast between positive and negative aspects, but the second sentence specifically refers to "these same adaptations," not a contrasting idea. When you see "these same [things]" in the second sentence, it often signals that you need a consequence transition rather than a contrast transition.

The relationship is contrast—the first sentence presents GDP growth as a useful proxy, while the second points out its significant limitations. The second sentence explains how GDP "can increase even when" negative things happen, directly challenging its reliability as a well-being measure. Choice A "However" correctly signals this shift from presenting GDP's common use to critiquing its limitations. Choice B "Accordingly" would incorrectly suggest the limitations follow logically from its use as a proxy, rather than undermining it. Economic indicator discussions often follow this pattern: common use BUT hidden flaws.

The relationship is concession or contrast—despite the usefulness of simplifying assumptions mentioned in the first sentence, they can lead to errors in certain conditions. The first sentence acknowledges the value of simplifications, but the second warns about their limitations. Choice C "Nonetheless" correctly signals this "despite the benefits, there are limitations" relationship. Choice B "Therefore" would incorrectly suggest the errors are a direct logical consequence rather than an unfortunate limitation. In scientific contexts, watch for this pattern: "X works well for Y" followed by "when applied to Z, problems arise"—this calls for a concession transition.

The relationship is contrast—the first sentence presents a positive interpretation of children's errors (showing pattern learning), while the second points out a negative consequence (reduced communication accuracy). The phrase "the same tendency" followed by "reduce communication accuracy" signals we're discussing a downside of the phenomenon. Choice B "However" correctly captures this shift from positive linguistic insight to practical communication problem. Choice A "Therefore" would incorrectly suggest reduced accuracy is a logical goal, rather than an unfortunate side effect. Linguistic examples often follow this pattern: interesting phenomenon BUT practical drawbacks.