Question ID:PT36 S3 Q26 Passage:Before 1986 physicists believed they could describe the universe in terms of four universal forces.  Experiments then suggested, however, a fifth universal force of mutual repulsion between particles of matter.  This fifth force would explain the occurrence in the experiments of a smaller measurement of the gravitational attraction between bodies than the established theory predicted. Stem:Which one of the following, if true, most strengthens the argument that there is a fifth universal force? Correct Answer Choice:BChoice A:The extremely sophisticated equipment used for the experiments was not available to physicists before the 1970s. Choice B:No previously established scientific results are incompatible with the notion of a fifth universal force. Choice C:Some scientists have suggested that the alleged fifth universal force is an aspect of gravity rather than being fundamental in itself. Choice D:The experiments were conducted by physicists in remote geological settings in which factors affecting the force of gravity could not be measured with any degree of precision. Choice E:The fifth universal force was postulated at a time in which many other exciting and productive ideas in theoretical physics were developed.