Question 35·Medium·Inferences
An early medieval chronicle describes "a sunless year." Some climatologists have interpreted this as evidence of a major volcanic eruption, but climate historian Dr. Mei Kwan notes that chroniclers often used such phrasing for extended cloud cover from monsoons or dust storms; moreover, tree-ring records from the region show only modest growth reductions during that decade. The chronicle’s description, therefore, _____
Which choice most logically completes the text?
For “complete the text” inference questions, first identify the logical structure: look for contrast words like “but” and conclusion words like “therefore” to see whose viewpoint drives the blank. Paraphrase the key evidence in your own words and decide whether it strengthens, weakens, or limits a claim. Then quickly eliminate answer choices whose strength (“proves,” “rules out,” “contradicts”) does not match the passage’s tone or evidence, and pick the one that captures the author’s actual conclusion as precisely—but not more strongly—than the text supports.
Hints
Pay attention to the contrast word
Focus on the word “but” in the sentence. It shows that Dr. Kwan is responding to and challenging the first interpretation. The conclusion should follow from her perspective.
Ask what Kwan’s evidence does to the volcanic-eruption idea
Kwan points out that the phrase “a sunless year” was used in other weather situations and that tree-ring records show only modest effects. Does this make the volcanic-eruption explanation completely certain, completely wrong, or just less certain?
Check the strength of each answer choice
Look for words like “proves,” “contradicts,” or “rules out” in the choices. Ask yourself: does the passage really give that strong a level of certainty, or does it suggest something more cautious?
Step-by-step Explanation
Identify whose reasoning leads to the conclusion
The first sentence describes how some climatologists interpret the chronicle as evidence of a major volcanic eruption. Then we see the word “but”, which signals a contrast, and we are introduced to Dr. Mei Kwan, who provides additional information.
Because the sentence ends with “therefore, _____”, the blank must be filled with a conclusion that follows from Kwan’s points, not from the climatologists’ original interpretation.
Summarize Dr. Kwan’s two key points
Kwan makes two arguments that weaken the idea that the chronicle clearly shows a volcanic eruption:
- Chroniclers often used wording like “a sunless year” to describe extended cloud cover from monsoons or dust storms, not just volcanic events.
- Tree-ring records from the region show only modest growth reductions during that decade, not the dramatic changes you might expect from a huge eruption.
Together, these show that the chronicle’s wording is ambiguous and the physical evidence is weak for a major eruption.
Decide what kind of conclusion follows
Kwan is not saying she knows exactly what caused the “sunless year,” nor that the chronicle is wrong. Instead, she is arguing against overconfidence in the volcanic-eruption explanation.
So the conclusion should express that the chronicle’s description does not provide strong, definitive proof of a major volcanic eruption, especially when considered alone.
Match the conclusion to the answer choices
Now compare the choices to that idea:
- Some choices use very strong language like “proves” or “rules out,” which do not match Kwan’s cautious tone.
- Only one choice correctly says that the chronicle’s description on its own is not conclusive proof of a major volcanic eruption.
Therefore, the correct completion is: “is not, by itself, conclusive evidence that a major volcanic eruption occurred that year.”