What type of committee is appointed temporarily to complete a specific task?

A committee appointed temporarily to complete a specific task is best described as an Ad Hoc committee. This type of committee is created for a particular purpose and is dissolved once that purpose has been achieved. The term "ad hoc" itself means "for this" in Latin, indicating that the committee is formed to address a specific issue or project that may not fit neatly into the ongoing work of the organization or its permanent committees.

In contrast, other types of committees such as interim committees are generally established to hold meetings or carry on business between regular sessions, while special committees may also refer to those formed for specific tasks but often encompass a broader scope or ongoing responsibilities. An informal committee typically lacks formal recognition or structure, making it distinct from the structured approach seen in ad hoc committees.

Thus, the Ad Hoc committee stands out by being directly linked to completing a targeted task in a temporary manner, aligning perfectly with the question’s requirement.