Suppose That a Doctor Decides That a Patient Has a Cold,rather

Suppose that a doctor decides that a patient has a cold,rather than a much rarer disease,Disease X.She decides the disease is a cold,even though one symptom is fairly typical of Disease X and fairly atypical of a cold.This doctor is

A) paying attention to the base rate of the diseases.
B) showing the confirmation bias.
C) demonstrating the small-sample fallacy.
D) combining the availability heuristic with the representativeness heuristic.