It says mean, but the variable being compared here is not a scaled value. If it were comparing the mean blood pressures between Asians and Americans, then it would have been a comparison of means. You can construct a 2x2 table to visualize it. When you do, it becomes clear that you'd use the chi-squared test.
Yeah, it is weird wording to me because chi square would be my first thought. Not sure what they mean by "mean" that's why I was thinking the other way maybe. Percentage makes it seem chi square. Hopefully, this is not a kind of question that will show up. I think it is poorly worded. Or unless that is the point.