The best strategy to use for writing down questions you have while reading is B: annotating.
When you annotate, you actively engage with the text by making notes in the margins, highlighting important points, and writing down any questions, thoughts, or connections that come to mind as you read. This process helps deepen your understanding of the material and allows you to track your thoughts and inquiries effectively.
While the other strategies (A: illustrating, C: visualizing, and D: freewriting) can also be helpful in various contexts, annotating is particularly effective for directly capturing questions related to the text.