I can't tell by wing shape but when I enlarge the image there is a small fourth mark/ slash on the forewing adjacent to the three large horizontal spots which occurs with Question Mark.

and the faint fourth slash is apparently a regional subspecies variation.
The specimen in question has characteristic summer form of Question Mark with color, shape, tail length, and indention depth between tail tips of the hindwing.

They both have the forewing slash, yet literally every other characteristic (wing shape, the "comma" marking, etc.) indicates that they are comma.

http://butterfliesofamerica.com/polygonia_comma_specimens2.htm

I fully agree with Alex. The hind wing shape is clearly a comma, and is the underside pattern. Extent and size of markings in anglewings is highly variable and not consistent. Phyciodes species (crescents) are far worse in that regard. I have seen hundreds of questions marks, but never one that looked like this.

Polygonia comma - hind wing tails very short, trim on hind wing very thin and whitish rather than thick and pinkish to purplish, trim ccompletely covering less than a quarter the length of the tail, as opposed to about half the length, pair of black spots on hind wing completely separate from blackish region on hindwing as opposed to both being partially enveloped in it, and I could go on.

P. interrogationis http://www.butterfliesofamerica.com/L/t/Polygonia_a.htm. Variation between these species makes ID difficult and usually based on FW extra slash mark or ventral sign mark.

specimen with a flat straight border between the outer tip and tail of the hindwing. Looking at summer form Question Mark images in BugGuide http://bugguide.net/node/view/487/bgimage supports this observation. Although referenced, I do not see a ventral image which would be helpful.