A 2023 study tested whether listing job salary ranges in postings increased applicant counts. Researchers compared four city job markets that adopted the practice in different years and reported applicant counts (in thousands per month) one year before and one year after adoption: City A, 24 → 36; City B, 32 → 35; City C, 18 → 30; City D, 41 → 44. They also reported the same data for control cities that <em>never adopted</em> the practice over the same windows: A's control, 25 → 27; B's control, 33 → 36; C's control, 19 → 21; D's control, 42 → 45. The researchers concluded that the policy worked in some cities but not others, suggesting context matters. The data uniquely supporting a real policy effect in <em>only</em> certain cities is ______
Which choice most logically completes the text using the data above?
- A
the post-policy applicant counts in all cities.
- B
the policy cities' average gains.
- Ccheck_circle
the contrast: City A and City C's policy gains (12 thousand each) far exceed their control's modest 2 thousand gains, while Cities B and D's policy gains (3 thousand each) match their controls' similar gains.
- D
the highest absolute applicant count after policy adoption.
Explanation
To argue the policy worked only in some places, you need each policy city's change compared with its control. Choice B does this for all four pairs and shows large excess gains only in A and C, exactly supporting the "worked in some, not others" claim.