please answer

Dr. Adam wants to know how time spent practicing the piano affects piano playing ability. To do so, he conducts an experiment with three groups who practice for different amounts of time: one hour, two hours, and three hours. Dr. Adam performs an ANOVA. Here is a summary of his data: Groups One Hour Two Hours Three Hours n -50 n = 50 n -50 M - 30 M - 43 M-55 SD - 4 SD - 3 SD-15 Which assumption of an ANOVA is most likely to have been violated given the data presented? C Homogeneity of variance Subjects are selected using random sampling Independence of observations O Normality of distribution