If the Schedule B does not apply to your return and you do not need to file it, you must check the box at the top of Schedule B to indicate so. Directly under the Name of the Organization there is a check box for "Check if the organization is not required to attach Schedule B (Form 990 Return of Organization Exempt From Income Tax, 990-EZ Short Form Return of Organization Exempt From Income Tax, or 990-PF Return of Private Foundation). Once this box is checked, the box on Form 990-PF Part I Line 2 will be checked as well.
To enter or review information on Schedule B:
Per IRS Instructions for Form 990 Return of Organization Exempt From Income Tax, on page 4:
In general, first complete the core form, and then complete alphabetically Schedules A–N and Schedule R, except as provided below.
Note that any link in the information above is updated each year automatically and will take you to the most recent version of the document at the time it is accessed.