All I have is my personal experiences to go on but as a white guy I was never asked that question while a CS undergrad - and that was in Texas where people are

All I have is my personal experiences to go on but as a white guy I was never asked that question while a CS undergrad - and that was in Texas where people are extremely polite and helpful to strangers. It's fairly simple. Young students are often spotted trying to find some location on campus. There aren't as many women taking CS. Even fewer black women. Therefore people's expectations upon seeing a young black woman in the CS department is that she's lost. That does not make those people racist and I didn't think the author was claiming any such thing. It may mean the system as a whole is racist or perpetuating older racist policies through societal inertia. When those problems are solved we would expect the percentage of black female CS students to roughly track the general population... Then they won't be unicorns and people's default expectations will change.