Question

Marie, a witness in a criminal case, is called to testify. During cross-examination, the defense counsel raises an objection to Marie's testimony, citing her disqualification as a witness under Section 21 of the Rules of Court. The defense counsel argues that Marie's testimony should be excluded due to her relationship with the accused.

On the other hand, the prosecutor contends that Marie is qualified to testify, as her relationship with the accused does not fall under the disqualification provided in Section 21. The prosecutor supports this argument by referring to Section 23 of the Rules of Court.

What are the qualifications and disqualifications of witnesses under Sections 21-24? Discuss the applicability of these provisions to the situation of Marie as a witness in the criminal case.