14. The prosecutor has presented evidence showing that the son has personal knowledge of the incident, understands the oath to testify truthfully, and has the cognitive ability of a seven-year-old. The son's testimony should be

B is correct. Every person is competent to be a witness, as long as the person meets the requirements of having personal knowledge and taking the oath to testify truthfully. A witness may not testify to a matter unless evidence is introduced sufficient to support a finding that the witness has personal knowledge of the matter. In addition, before testifying, every witness shall be required to declare that the witness will testify truthfully, by oath or affirmation administered in a form calculated to awaken the witness's conscience and impress the witness's mind with the duty to do so. Because the prosecutor has admitted evidence providing a sufficient basis for believing the son has personal knowledge and understands his obligation to testify truthfully, the son's testimony should be admitted.

A is incorrect. It misstates the requirements of the fitness for a witness to testify.

C is incorrect. The son's age is irrelevant to whether his testimony is probative, and because the son's testimony that he saw the defendant shoot him and his father is clearly highly probative to the case.

D is incorrect. The son's testimony is highly probative to the case and is not unfairly prejudicial. The son's testimony is certainly detrimental to the defendant's case, but it is not unfairly prejudicial.