Which term relates to a duty or responsibility one must fulfill?

The term that relates to a duty or responsibility one must fulfill is "Obligation." An obligation signifies a commitment or requirement that an individual or group is bound to uphold. This can stem from moral, legal, or social responsibilities. For instance, one might have an obligation to complete certain tasks at work, pay bills, or adhere to promises made to others. In essence, it encapsulates the idea of being held accountable for certain actions or duties.

The other terms do not convey the same meaning. "Premonition" refers to a feeling or intuition about a future event, typically signaling something bad. "Innocuous" means harmless or not likely to provoke a strong reaction. "Nullify" involves the act of canceling something out or rendering it void, which does not relate to the concept of responsibility or duty.