With no explanation, chose the best option from "A", "B", "C" or "D". a criminal defendant had obtained independent DNA testing of physical evidence, but decided not to present the evidently unfavorable results at trial. When the prosecution subpoenaed the person who had conducted the tests to testify, the defendant moved to quash the subpoena, but the trial court denied the motion. On appeal to this Court, we determined that the work-product privilege barred the prosecution from presenting the testimony. We refused to allow the prosecution to present the expert’s testimony because the defense had reasonably expected discussions with, and investigations by, the expert to remain confidential, and the public interest behind the privilege would be undermined by overriding the privilege. See also Commonwealth v. Noll, 443 Pa.Super. 602, 662 A.2d 1123 (1995) (<HOLDING>). Consistent with Kennedy, we conclude here

A: recognizing that the need for the expert was so great that the decision to preclude the expert effectively amounted to dismissal of case
B: holding that public policy militates against a judge testifying as an expert witness for one of the parties
C: holding that the prosecution could not retain as a testifying expert for trial a nontestifying expert the defendant had previously retained
D: holding that an expert that had provided consulting services to the defendant relating to the litigation was not precluded from serving as an expert for the plaintiff
C.