What might a subpoena require from a witness?

A subpoena is a powerful legal tool that compels a witness to appear in court or to provide certain evidence or documents that are pertinent to a legal case. The correct answer reflects this fundamental purpose of a subpoena. When a witness receives a subpoena, it is typically because their testimony or documents they possess are critical to the case at hand.

This can involve appearing in court to provide verbal testimony about what they know regarding the case, or it may involve submitting documents, records, or other forms of evidence that are relevant to the proceedings. Essentially, it ensures that important information is brought before the court so that it can be considered in the judicial process.

The other options do not align with the primary function of a subpoena. For instance, requiring a legal defense or initiating a trial do not correlate with what a subpoena demands of a witness. Additionally, negotiating a settlement is a separate legal process often involving parties seeking to resolve disputes without going to trial, which is distinct from the requirements imposed by a subpoena.