According to the passage, random failures in automatic control systems are "not merely trivial aberrations" because A. automatic control systems are designed by engineers who have little practical experience in the field B. the failures are characteristic of systems designed by engineers relying too heavily on concepts in mathematics C. the failures occur too often to be taken lightly D. designers of automatic control systems have too little training in the analysis of mechanical difficulties E. designers of automatic control systems need more help from scientists who have a better understanding of the analytical problems to be solved before such systems can work efficiently