What part of a literature review that defines the central problem or the focused research question

The introduction of the review

Explanation:

In simple words, Although it may seem unnecessary to "promote" the subject in the opening, many writers do not do so. Allow the reader to learn about the topic's history, describe words that they may not be acquainted with, clarify the range of the debate, and your motivation for publishing the review.

The topic as well as its limitations should be stated clearly in the beginning. In some manner, you should explain why the study field is essential, intriguing, troublesome, or relevant. A dissertation or thesis's literature review is a crucial component. It must be comprehensive and precise.