H-4 I539 part 4 question 3c

I filed I485 for both my wife and me a few weeks ago. Now I am applying H-1 and my wife will apply H-4 using I-539 form. In the I539 form, there is a question (3c) in part 4: Has a form I-485 ever been filed by you. I anwsered yes. Do I need to explain it in a seperate page and write the I-485 receipt number? Does this matter? Thx.