Which of the Following Statements About Polygraph Examinations Is True

Which of the following statements about polygraph examinations is true?

A) The physiological indicators measured by the polygraph can be altered by conscious efforts through cognitive or physical means.
B) Advocates claim that polygraph examinations are accurate in more than 90 percent of criminal and employment cases if interpreted by a competent examiner.
C) Critics claim that the tests are accurate only two-thirds of the time and are far more likely to be unreliable for a subject who is not telling the truth.
D) Polygraph accuracy for screening purposes is almost certainly higher than what can be achieved by specific-incident polygraph tests.