Duane Teaches in an Industrial City Where Residents Are Concerned

Duane teaches in an industrial city where residents are concerned about groundwater contamination. Duane is elected president of a citizens' environmental group that some residents consider controversial. Near the end of the school year, Duane's principal quietly tells him that he will not be offered a third-year teacher's contract because of his reputation as a "radical environmentalist." Which of this teacher's rights has been violated?

A) The everyday ethics of teaching
B) The right to substantive due process
C) The right to a teaching contract
D) The right to procedural due process