A 62-year-old man with symptomatic heart failure is enrolled in a randomized controlled trial comparing a novel ACE inhibitor (Drug A) to standard therapy (Drug B). He is randomized to receive Drug A. After 8 weeks of treatment, his New York Heart Association functional class improves from class III to class II, with objective improvement in ejection fraction on echocardiography. When asked about his clinical improvement during follow-up, the patient states: 'My symptoms improved because I've been much more disciplined with my diet and exercise routine. The medication probably didn't make much of a difference.' His wife notes he has had inconsistent medication adherence and minimal change in dietary habits compared to baseline. Which of the following cognitive biases best explains this patient's attribution of his improvement?

1. A)Anchoring bias—the patient fixates on his initial baseline functional class and cannot adjust his perception despite objective improvement
2. B)Fundamental attribution error—the patient attributes his improvement to stable personal characteristics rather than situational factors like medication efficacy
3. C)Availability heuristic—the patient emphasizes diet and exercise because these interventions are more cognitively accessible than medication mechanisms
4. D)Recency bias—the patient weights his recent dietary efforts more heavily than his actual medication adherence over the past 8 weeks
5. E)Self-serving bias—the patient attributes his improvement to internal factors (adherence, diet) that enhance his self-image while minimizing the contribution of external factors (the medication)GABARITO