A Strange Detector Signal Renews Questions About Dark Matter

Study the questions and tasks

Work through the material below, or start the interactive practice above to complete an attempt. Try the exercises before opening any answer or transcript sections, then use them to review your work.

Practice level

B2. Try this level if you can follow the instructions and understand most of the language; choose an earlier level if you need more support.

Question formats

Single choice

How to approach this practice

Read the passage for its main idea, then return to the relevant sentence or paragraph for each question. Base answers on the passage.

1. Question 1 · Single choice

   Choose one answer.

   What is the article’s main purpose?

   Return to the passage, recording or visual
   1. To announce a confirmed dark matter discovery
   2. To explain an intriguing but inconclusive signal
   3. To describe South Dakota’s laboratory facilities
   4. To compare competing detector technologies
   Check answers and explanations

   Answer

   To explain an intriguing but inconclusive signal

   It explains the signal’s significance while emphasizing that detection remains unconfirmed.

   For now, the South Dakota recording remains an intriguing possibility rather than a confirmed discovery.

2. Question 2 · Single choice

   Choose one answer.

   Why does the article mention that the blip could be a fluke?

   Return to the passage, recording or visual
   1. To show why the detector stopped working
   2. To explain why the signal remains uncertain
   3. To prove that dark matter is imaginary
   4. To criticize the scientists’ methods
   Check answers and explanations

   Answer

   To explain why the signal remains uncertain

   This possibility explains why the signal attracts interest but cannot prove detection.

   The event could prove important, but it could also be a fluke.

3. Question 3 · Single choice

   Choose one answer.

   What does “both possibilities” refer to?

   Return to the passage, recording or visual
   1. Two different researchers discussing the signal
   2. Two possible explanations for the event
   3. Two locations connected with the report
   4. Two methods for detecting dark matter
   Check answers and explanations

   Answer

   Two possible explanations for the event

   The phrase refers to the event being important or merely accidental.

   Researchers must consider both possibilities as they assess what happened.

4. Question 4 · Single choice

   Choose one answer.

   How is the article organized?

   Return to the passage, recording or visual
   1. From historical background to political consequences
   2. From initial event to interpretation and cautious conclusion
   3. From laboratory design to detailed mathematical results
   4. From confirmed findings to rejected theories
   Check answers and explanations

   Answer

   From initial event to interpretation and cautious conclusion

   It moves from the signal and uncertainty toward broader scientific implications.

   The discussion presents the signal as part of a broader effort to understand whether dark matter can be detected.

5. Question 5 · Single choice

   Choose one answer.

   What broader issue does Natarajan’s participation highlight?

   Return to the passage, recording or visual
   1. How scientific evidence gains sufficient strength
   2. Why theoretical physicists avoid public discussions
   3. How detectors are constructed underground
   4. Why NPR reports focus on technical subjects
   Check answers and explanations

   Answer

   How scientific evidence gains sufficient strength

   Her perspective connects one result with standards for drawing scientific conclusions.

   Her discussion with Detrow connects the technical question of one detector’s unusual result with the larger challenge of deciding when evidence is strong enough to support a scientific conclusion.

6. Question 6 · Single choice

   Choose one answer.

   What can useful questions accomplish despite an unexplained passage?

   Return to the passage, recording or visual
   1. They can replace the need for further experiments
   2. They can guide investigation of possible explanations
   3. They can confirm the detector’s original design
   4. They can guarantee a scientific conclusion
   Check answers and explanations

   Answer

   They can guide investigation of possible explanations

   They can support investigation without establishing that dark matter was detected.

   In that context, even an unexplained recording can lead to useful questions.

7. Question 7 · Single choice

   Choose one answer.

   What condition determines whether the passage becomes important?

   Return to the passage, recording or visual
   1. Whether journalists publish additional interviews
   2. Whether scientists interpret it as meaningful evidence
   3. Whether South Dakota expands its laboratories
   4. Whether the detector records another location
   Check answers and explanations

   Answer

   Whether scientists interpret it as meaningful evidence

   Its importance depends on interpretation and whether it exceeds an isolated fluke.

   Its importance depends on how scientists interpret the signal and whether it can be understood as more than an isolated fluke.

What to review next

Find the words that support each answer. For a mistake, compare the question with the evidence and identify the detail or inference you missed.

A focused practice result shows how you did on these tasks. Use several activities across skills to decide what to study next; one practice score does not certify an overall CEFR level.

Before you practise: a worked example

Look for evidence in the text. Separate what the writer says from what you already know about the topic.

The library normally closes at six, but on Fridays it stays open until eight. When does it close on Friday?

The answer is eight. But introduces an exception to the normal closing time, so the first time mentioned is not the answer.

This teaching example is separate from the scored questions. After your test, compare any mistakes with the explanation and revisit the topic before trying again.