In Which of the Following Situations Is the Assumption of Linearity

Multiple Choice

In which of the following situations is the assumption of linearity violated?

A) Trend analysis shows that there exists a significant quadratic trend.
B) There is no association between the independent variable and the covariate.
C) The distribution of the covariate is seriously skewed in all groups.
D) The scatterplot of the dependent variable and the covariate is U shaped for all groups.