Read the passage and answer the question.
A linguist analyzing changes in coastal dialects compiled a corpus of recorded interviews from the town of Greyhaven. The corpus consisted of 96 interviews: 48 recorded in 1975 and 48 recorded in 2015. Each interview lasted exactly 30 minutes, and all speakers were lifelong residents of Greyhaven. The linguist focused on the pronunciation of the vowel in words like "boat" and coded each instance as either a "raised" or "non-raised" variant. In the 1975 recordings, 31% of coded instances were raised; in the 2015 recordings, 54% were raised. The study explicitly noted that the 2015 speakers had a higher average level of formal education than the 1975 speakers, but it did not provide the education averages. The linguist also stated that the interviews were conducted by different fieldworkers in the two years.
According to the passage, which of the following is true?
- All interviews in the corpus were recorded in 2015.
- In the 2015 recordings, 54% of coded instances were classified as raised. (correct answer)
- The study reported exact average education levels for both speaker groups.
- Each interview lasted 45 minutes.
- The same fieldworker conducted the interviews in both 1975 and 2015.
Explanation: This question tests detail comprehension by asking which statement is true according to the passage. Correct answers in such questions restate explicit information from the text without adding inferences or external knowledge. The relevant detail is in the sixth sentence, which provides the percentages of raised vowel variants in the recordings. This sentence states that in the 2015 recordings, 54% of coded instances were raised. Choice B matches this text exactly by restating the year and the 54% figure for raised instances. A representative distractor, like choice D, fails because it introduces a specific interview length of 45 minutes, whereas the passage explicitly states each lasted exactly 30 minutes. This distractor alters a stated detail to create confusion.