Which term denotes a lack of care in performing one's duties?

The term "remiss" specifically refers to a failure to fulfill one's duties or responsibilities due to a lack of care or attention. It describes a state of negligence or inattentiveness in performing tasks that one is expected to complete. This aligns perfectly with the context of the question, which focuses on a lack of care in duties.

The other terms have distinct meanings that do not relate to carelessness in performing duties. “Temerity” refers to excessive confidence or boldness, often in an audacious or rash manner. “Pungent” describes a strong smell or taste, typically something that is sharply or intensely perceivable, and is not related to duties. “Virulent” describes something that is extremely harmful or hostile, particularly in the context of diseases or toxins, without any direct correlation to negligence or care in fulfilling responsibilities.