With no explanation, label text_A→text_B with either "DON'T KNOW", "NO" or "YES".
text_A: Although flatus possesses an odor, this may be abnormally increased in some patients and cause social distress to the patient. Increased odor of flatus presents a distinct clinical issue from other complaints related to intestinal gas. Some patients may exhibit over-sensitivity to bad flatus odor, and in extreme forms, olfactory reference syndrome may be diagnosed. Recent formally-funded research has found a correlation between flatus odor and both loudness and humidity content
text_B: Given the way this research was conducted, is it likely that participants were compensated, and that other difficult but necessary precautions were taken such as eliminating as many variables as possible, using a representative sample, etc.
YES.