Which of the following written test item types is least likely to suffer from guesswork issues?

Essay questions are least likely to suffer from guesswork issues because they require students to construct a response based on their understanding and knowledge of the material, rather than selecting from predetermined options. This type of assessment evaluates the depth of a student's comprehension and their ability to articulate thoughts clearly and coherently. Since essay questions demand a thoughtful and detailed response, chance plays a minimal role in determining a student's success; instead, performance is more closely aligned with their actual learning and comprehension.

In contrast, true/false and multiple-choice questions provide limited options, making it easier for students to guess the correct answer without truly understanding the material. Fill-in-the-blank questions might also allow for guessing, especially if there are contextual clues or if the student is familiar with similar terms. Therefore, essay questions stand out as a method of assessment that effectively minimizes the impact of random guessing on performance outcomes.