Tab stops are very useful when you want to a. align text into rows. b. add space between paragraphs. c. align text into columns. d. add indents to quotes.

The best answer here is Answer C - Tab stops are useful when you want to "align text into columns".

All tab stops do is shift text a fixed amount to the left or right on the line. They are useful for improving the layout of text when you want to align multiple rows.

Answer A is incorrect because rows are vertical and not horizontal. B is also irrelevant because spaces between paragraphs are vertical. Answer D could also be correct because you can use tab stops to indent text aswell, but the more general answer is A. If you can have more than one answer, you could have A and D.