Researchers Interested in the Effects of Sesame Street on Children's

Researchers interested in the effects of Sesame Street on children's reading level randomly assign a number of children to one of four groups: one group is required to watch 2 hours of Sesame Street each week, a second group watches 4 hours, a third group watches 8 hours, and a fourth group watches 10 hours. After 6 months, the researchers re-administer a reading test to all children and compare the scores of the children in the different groups. What is the independent variable in this study?

A) the children
B) the amount of Sesame Street the children viewed
C) children's performance on the reading test
D) the level of attention the children paid to Sesame Street while they watched it