Question: Review the statement below. What is the effect of `covariate:factor` on the analysis?

  1. It forces the intercepts of the individual regressions to zero.
  2. It calls for the effect of the covariate **within each level of the factor**.
  3. It calls for the effect of each variable from covariate to factor in testcoef.
  4. It forces the covariate to enter the equation before the factor levels.

Answer: The correct answer of the above question is Option B:It calls for the effect of the covariate **within each level of the factor**.