What must be shown to prove breach of duty in a negligence case?

To demonstrate breach of duty in a negligence case, it is essential to establish that the defendant's actions were unreasonable under the circumstances. This involves showing what occurred in the situation leading to the alleged negligence, particularly focusing on whether the defendant failed to act as a reasonably prudent person would have in similar circumstances.

In negligence law, the standard of care is typically defined by what a reasonable person would do to avoid harming others. Therefore, if the defendant's conduct deviated from this standard—meaning they acted unreasonably—this constitutes a breach of duty. The plaintiff must illustrate this unreasonableness by presenting evidence of the specific actions or inactions of the defendant that led to the claim of negligence.

The other options do not accurately capture the necessary elements to prove breach of duty. Simply showing that the plaintiff was harmed, having direct evidence of harm, or proving a prior relationship with the defendant does not inherently address whether the defendant acted unreasonably, which is a fundamental aspect of proving a negligence claim. Thus, demonstrating what happened and highlighting the unreasonableness of the defendant's actions is crucial to establishing a breach of duty.