This photo was taken in Copenhagen, by someone who goes by Hanjosan on Flickr. The context of the photo is not given. We don't know where the women are or what they're doing. We don't know what their relationship is or how they're interacting. We don't know what their daily lives are like.
We read our own assumptions into those blank spaces. People look at the Muslim woman's inscrutable expression and see very different things.
"She doesn't look happy."
She looks "timid."
"She looks like she wanted to cry at any minute. Maybe she knows what will come if she gets home..."
"She has a look on her face like 'Where's the stone gonna be coming from???'"
She's a "brave girl."
"This sista's got the sass!"
"This girl is a badass. I would not fuck with her."
"The girl holds onto her values but somehow makes her look and her life her own."
What we think we already know determines what we make of new information. Our prejudices are self-reinforcing. We construct other people in our minds and determine who they are before we ever meet them.
If you're reading this blog, you've likely experienced this truth. The different comments that this photo has received are just another demonstration of that.