What item must not have an eraser when using the materials for CD?

The correct answer highlights the importance of using a #2 pencil without an eraser during the testing process to maintain the integrity and authenticity of the answers provided by the test-taker. When conducting assessments like those using the WISC-V, the absence of an eraser helps prevent the possibility of altering responses after they have been marked. This is crucial for ensuring that the score accurately reflects the child's abilities without any unintended modifications.

Test materials such as the response booklet, stopwatch, and manual serve specific purposes that do not relate to the method of responding during the test. The response booklet is where answers are recorded, while the stopwatch is used to time different sections of the test. The manual serves as a guide for the administrator but does not interact with the responses themselves. Thus, the emphasis on using a pencil without an eraser ensures that responses are permanent and can be evaluated in their original form.