In a recent study of arthritis, researchers tried but failed to find any correlation between pain intensity and any of those features of the weather -- humidity, temperature swings, barometric pressure -- usually cited by arthritis sufferers as the cause of their increased pain. Those arthritis sufferers in the study who were convinced of the existence of such a correlation gave widely varying accounts of the time delay between the occurrence of what they believed to be the relevant feature of the weather and the increased intensity of the pain. Thus, this study __. Of the following, which one most logically completes the argument? ["indicates that arthritis sufferers' beliefs about the causes of the pain they feel may affect their assessment of the intensity of that pain", 'indicates that the weather affects some arthritis sufferers more quickly than it does other arthritis sufferers', 'suggests that arthritis sufferers are imagining the correlation they assert to exist', 'suggests that some people are more susceptible to weather-induced arthritis pain than are others']