Which of the following is NOT a part of a peace officer's authority?

Making arrests on-duty is a fundamental authority granted to peace officers, allowing them to enforce the law and apprehend individuals suspected of committing crimes. Transporting suspects is also a critical responsibility that involves safely moving individuals who have been arrested or are involved in legal proceedings.

Taking custody of personal firearms can be part of a peace officer's duties, particularly in situations involving domestic violence or when a person may pose a risk to themselves or others. However, this authority is typically exercised under specific legal guidelines and is not as universally applicable as the other functions listed.

The execution of search warrants is a judicially sanctioned act that requires a warrant issued by a judge based on probable cause. In the context of peace officers, while they may assist in this process, the actual execution of search warrants is generally reserved for law enforcement agencies such as police. This distinction clarifies why this option may not represent a typical or direct responsibility of peace officers in the same manner that making arrests or transporting suspects does.