According to Rule 613(b), calling and/or examining a witness by the court is not allowed.

• A. The court may call or examine a witness
• B. The court's calling or examining is permitted only with party consent
• C. Calling and/or examining a witness by the court is not allowed
• D. The court can only call a witness if both parties stipulate

Answer: (C)

The main idea is how Rule 613(b) governs impeachment by prior statements and keeps impeachment a matter for the parties, not the judge. Under this rule, the court does not call or examine a witness for the purpose of impeaching another witness. Impeachment proceeds through the witness's own testimony and cross-examination by the opposing party, with any allowed use of extrinsic evidence of a prior inconsistent statement conditioned on the witness having a chance to explain or deny and the adverse party having an opportunity to question. This design preserves the adversarial process and avoids the court stepping into a witness role. That’s why the statement that calling or examining a witness by the court is not allowed best fits Rule 613(b); the other options would grant the court authority or require consent/stipulation, which aren’t features of this rule.