In NYC's restaurant letter-grade system, what does a grade of 'A' posted in the window indicate?

解析

In NYC, the Health Department assigns sanitary inspection scores based on violation points, and the lowest point range earns an 'A' — the best grade — which must be posted where the public can see it. More violation points result in a 'B' or 'C' grade. An 'A' signals the strongest inspection result, not a failure or closure.