Professor Stevens, the Great English Scholar, Says That Chaucer's Canterbury

Professor Stevens, the great English scholar, says that Chaucer's Canterbury Tales represents a milestone in the development of the English language. Therefore, the Canterbury Tales must indeed be a milestone, just as he says.

A) Appeal to force.
B) No fallacy.
C) Amphiboly.
D) Appeal to unqualified authority.
E) False cause.