According to the passage, the major reason that the evidence for the cold fusion phenomenon is suspect is（）

A．no existing theory can explain the evidence produced by cold fusion experiments
B．the excess production of energy associated with certain cold fusion experiments owe primarily to experimental error
C．too many energy-balance measurements have indicated excess energy, instead of evenly distributed experimental error
D．the total input power in cold fusion experiments has been too low to draw solid conclusions about the fraction of excess power
E． scientists too often regard these experiments as proof of "miracles"

The "cold fusion" phenomenon may be attributed to experimental errors mistakenly indicating an excess production of energy. Those theories explaining cold fusion require revisions in existing theories, and scientific skepticism Line requires that unless the experimental evidence justifies belief in these miracles, (5) one must conclude that experimental errors are being misinterpreted as positive proof of cold fusion’s possibility. One would expect half of all careful energy- balance measurements in cold fusion experiments to indicate excess energy, and about half to show an energy deficit, because experimental error spreads the results around the expected outcome. The recent preponderance of results (10) showing excess energy might indicate something new, but if one is deliberately searching for excess energy, then one may be able to "optimize" a complicated system to yield large amounts of apparent excess energy by fooling the measurement apparatus somehow. Whether a given excess-heat result represents a physical "miracle" or an experimental error is very difficult to (15) determine if the amount of excess heat is small or if the fraction of excess power to total input power is simply too low.