- AThe advertised number replaced one that had been answered at any hour of the day or night, and it is answered only between ten and twelve in the morning, when most of the town's residents are at work
- BThe department's own staff were told of the new number a week before it was advertised to the public
- CThe number was advertised in the newspaper as well as on the department's boards
- DFailures of supply are more frequent in the summer months than in the winter
Step-by-Step Solution
Complaints recorded and failures suffered are two different quantities, and a two-hour window that falls in working hours cuts the first without touching the second. The residents' troubles are unchanged; only their ability to report them has been narrowed. Telling the staff early and advertising widely would if anything raise the count of complaints, and the seasonal pattern of failures applies to the period before the change as much as after it.
Answer: A) The advertised number replaced one that had been answered at any hour of the day or night, and it is answered only between ten and twelve in the morning, when most of the town's residents are at work