January 22, 2016, NPR News Headline Reads "Why Poverty May

January 22, 2016, NPR news headline reads "Why Poverty May Be More Relevant Than Race For Childhood Obesity." The article states, "At first glance it looked like childhood obesity was more common among African Americans or Hispanics... When they accounted for poverty, though, the trend vanished." The study collected data on a random sample of K-12 students in Massachusetts. In this study, whether or not a child lives in poverty is an example of a

A) quantitative variable.
B) response variable.
C) confounding variable.
D) normal variable.