Final answer:
An expert opinion can sometimes instantly solve a claim due to the expert's specialized knowledge and the credibility that comes from consensus among experts. So, option 4 is correct.
Step-by-step explanation:
Evidence, testimony, witness, or expert opinion could all potentially resolve a claim on the spot, depending on the circumstances and the complexity of the issue at hand. However, expert opinion is often what can instantly settle a claim. An expert's testimony is based on their specialized knowledge, allowing them to provide authoritative answers to specific questions. Furthermore, if there is a consensus among experts on a subject, and the provided testimony aligns with that consensus, it greatly increases the likelihood that the claim can be resolved quickly.
Experts are considered reliable because of their education, experience, and knowledge in a specific area. They also typically have a good sense of the answer to a question before a detailed analysis is conducted. In legal settings or academic discussions, the credibility of an expert may be evaluated based on their history, potential biases, motives, and how well their testimony matches with other experts or evidence. Concrete evidence that is measurable and can be tested experimentally is also highly compelling, but it is an expert opinion that often has the unique capacity to promptly settle a claim.