Researchers put two electrodes in a pool that a dolphin swam in. When the dolphin swam near the electrodes, the researchers would sometimes create a weak electric field by activating the electrodes. The dolphin would swim away if the electrodes were activated; otherwise it acted normally. The researchers then placed a plastic shield over small organs called vibrissal crypts located on the dolphin' s snout. With the crypts covered, the dolphin no longer swam away when the electrodes were activated. The statements above, if true, most strongly support which one of the following? ['In the wild, dolphins sometimes encounter strong electric fields.', 'Under normal circumstances, dolphins are unable to sense electric fields.', 'Vibrissal crypts enable dolphins to sense electric fields.', "Electric fields interfere with the normal functioning of dolphins' vibrissal crypts."]