For all four letters, AC is a better match. Especially the 'a'
Now what I mean by that is that, because the sample is very poor quality, we can't go on "details" like the appearance of roundness at the terminals -- which can be entirely the result of pixelation.
We must go by overall letter shape. The Cataneo 'a's overall shape has strokes that are straighter and change direction more extremely. The AC 'a' overlaid on the sample would fit perfect. Same with the 'y'. The 's' is close in both cases, but the AC 's' is just a little more rounder, like the sample.
I don't have the font, since I don't use a Mac, but it also stands to reason that since the other font has already been identified as a Mac-OS font, then chances are really, really good, this is AC, also a Mac-OS font.