Answer: The best resource to develop a differential diagnosis is the physical examination and the medical history.
Step-by-step explanation:
Possessing knowledge of different diseases, shows its applicability when performing the physical examination, which allows you to recognize the semiology studied in the patient and when observing it, be inclined to different diagnoses, I discard the other possibilities because, diseases may not require for its diagnosis Know the vital signs or the reading of capnography or a cardiac monitor, that although they are very useful, the diagnosis must be based on the clinic, currently these become aids, not being essential if the clinical suspicions or needs are not recognized of the patient, technology provides many resources, but the clinical history since antiquity is the basis for the study of a disease, without it the main data that inclines us to different diagnostic probabilities would not be known.