Which of the following terms indicates a high standard that must be met?

The term that indicates a high standard that must be met is "exact." This word is typically associated with precision and accuracy, signifying that something must adhere strictly to a defined standard or requirement without any ambiguity. When a standard is described as exact, it implies that there is little to no room for interpretation or error, highlighting the importance of meeting that specific criterion thoroughly.

Other terms in the question do not convey the same sense of rigor or precision. "Uncertain" refers to a lack of definite knowledge or assurance, while "imprecise" indicates a lack of accuracy and clarity, both of which are contrary to the notion of high standards. The term "relieved" suggests a feeling of reassurance or alleviation instead of denoting a standard that must be adhered to. Thus, "exact" stands out as the term that most clearly embodies the concept of a high standard that must be met.