Researchers tested whether mandatory financial-literacy classes improved adult savings rates. They compared four states that adopted mandates with matched non-mandate states. Average savings-rate change over 5 years: State 1, +1.4 points (vs. +1.5 points in non-mandate match); 2, +3.8 (vs. +1.0); 3, +1.0 (vs. +0.9); 4, +5.5 (vs. +1.4). The researchers argued the mandate was effective only in States 2 and 4. The data most uniquely supporting this is ______
Which choice most logically completes the text using the data above?
- A
the average gain across mandate states.
- B
State 1's smallest gain of 1.4 points.
- C
State 4's largest absolute gain of 5.5 points.
- Dcheck_circle
the contrast: States 2 and 4 outpaced their matched non-mandate states by 2.8 and 4.1 points, while States 1 and 3 nearly matched their controls' gains.
Explanation
"Effective only in States 2 and 4" requires comparing each mandate state to its matched control. Choice B does this across all four pairs and identifies the two with substantial excess gains, uniquely supporting the targeted claim.