Probably would be sufficient to just give a couple examples of what might constitute one of these.
Sorry, I know this is probably basic to someone who is in that field.
"In the US, XXX are much more likely to be unemployed than are YYY. The unemployment rate is defined as the percentage of jobless people who have actively sought work in the previous four weeks. According to the U.S. Bureau of Labor Statistics, the average unemployment rate for XXX in 2016 was five times higher than the unemployment rate for YYY"
"How much of this difference do you think is due to discrimination?"
In this case you'd fill in XXX and YYY with different values and show those treatments to your participants based on your treatment assignment scheme.