To modify a text box, you must first a. select the text box b. enter text c. right click and select modify d. select the format tab

The correct answer would be option A, Select the Text Box.

Explanation:

If you open a document and there are text boxes in it. You want to modify a text box, like if you want to delete the text or replace the text with new text, or want to change the font, or want to change the font size, or want to change the color of the text, you just need to select the text box which you need to modify. Then you can do whatever you want. You can start typing to change or edit the text, or can change the font or anything related to edit the text box.  So option A will be the appropriate answer.

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