Which of the following describes something that is neither needed nor essential?

The term "unnecessary" specifically refers to something that is not needed or essential, highlighting that it is superfluous or extraneous. In this context, it indicates that the item or situation in question does not contribute to the core requirements or functions necessary for a specific purpose or outcome. It conveys a clear understanding that the absence of this particular thing will not hinder progress or the performance of a function, aligning perfectly with the idea of something being neither needed nor essential.

In contrast, the other terms imply a degree of necessity or requirement. "Mandatory" indicates something that is required or obligatory. "Integral" refers to something that is essential or a vital component of a whole. "Indispensable" describes something that is absolutely necessary or cannot be done without. Therefore, each of these alternatives suggests importance or a necessity that "unnecessary" directly counters.