Which of the Following Is Not Considered by Johnson Et

Which of the following is not considered by Johnson et al. (1959) to be a major variable supporting his Diagnosogenic theory?

A) The listener's (parental) sensitivity, and overanxious reaction, to a child's disfluency,
B) The amount of time pressure involved in the conversation,
C) The overlap in the degree of disfluency between stuttering and nonstuttering controls,
D) The child's unfavorable reactions to his own disfluency, mirroring the parents' disappointment.