It's the middle one.
Panel 1: Elly holds out a pink shirt and tells Annie, who's holding a slobbering Christopher, that she bought it to wear at the clinic.
Panel 2: As she models it, she asks Anne what she thinks. Annie says nothing.
Panel 3: Elly then boasts that she won't have to wear the stuff she ususally wears for a whole week.
Panel 4: Realizing that that isn't much of an accomplishment, Annie tells a no-longer smiling Elly that she's merely exchanged one uniform for another.
Summary: It would have been a little bit nicer of Annie to let the idiot have her moment but when you realize that she's wondering how much Elly's spending is cutting into her profits, it's easy to see why she isn't as whippy about the pink shirt as Elly is.