A Cross-Filter allows a report to be filtered based on the child records of the primary object without displaying the child records themselves. The administrator can create an Account report and add two cross-filters: one for "Accounts with Opportunities" (filtered by this year's close date) and another for "Accounts with Activities" (filtered for completed tasks in the last 30 days). This configuration will produce a list of only the Account records that meet both criteria, fulfilling the request precisely.

A. Joined Report: This would show blocks for Accounts, Opportunities, and Activities, which is explicitly what the request wants to avoid (no opportunity details).

C. Summary Report: This report type groups rows of data but does not provide the "with/without" filtering capability needed to check for related records.

D. Filter Logic: This applies to standard filters on the primary object's fields, not for filtering based on the existence of related child records.

1. Salesforce Help. (2023). Filter Reports by Child Objects with Cross Filters. Salesforce. Retrieved from https://help.salesforce.com/s/articleView?id=sf.reportscrossfilters.htm&type=5. (This article explains the use case for cross-filters, stating, "Use a cross filter to fine-tune your results by including or excluding records from related objects and their children, without having to write formulas or code.")

2. Salesforce Help. (2023). Report and Dashboard Objects. Reports and Dashboards REST API Developer Guide. Retrieved from https://developer.salesforce.com/docs/atlas.en-us.apianalytics.meta/apianalytics/analyticsapireportanddashboardobjects.htm. (The documentation on report metadata describes crossFilters as a component for filtering by related objects.)