During the twentieth century, what was one reason that child care centers were created? a. the government mandated that centers opened. b. parents didn't want to care for children as much. c. women began to work during world war i and world war ii. d. there was an increased number of orphans.

Dr. redbull conducts a study to determine whether her new energy drink children perform better on spelling tests. she randomly assigns children to one of two groups: group 1 receives her energy drink and group 2 receives water. she then gives both groups a spelling test and compares the results. which of the following is true about this study? a. group 1 is the dependent variable and group 2 is the independent variable. b. this is a correlational study. c. group 2 is the experimental group. d. the independent variable is the type of drink the children receive.