Per the Form 990, Return of Organization Exempt From Income Tax Instructions:
Page 5: C. Sequencing List To Complete the Form and Schedules
In general, first complete the core form, and then complete alphabetically Schedules A–N and Schedule R, except as provided below (in instructions).
Page 82: Appendix E. Group Returns—Reporting Information on Behalf of the Group
In general, if a line requires a Yes/No answer and the answer isn't the same for all subordinate organizations to which the line applies, then check “Yes,” and explain the answer in the schedule's supplemental information section (if applicable) or in Schedule O (Form 990 or 990-EZ).