What tool should you use to define conditions for filtering contacts in Dynamics 365?

In Dynamics 365, to define conditions for filtering contacts, the Query tool is specifically designed for that purpose. This tool allows users to create complex queries to retrieve specific data by setting various criteria that match certain conditions. Users can utilize the functionalities of the Query tool to filter through large datasets, ensuring they can target particular subsets of contacts based on their attributes or behaviors.

While the Designer and Flow tools serve valuable functions within Dynamics 365—Designer typically allows for the creation and setup of marketing campaigns, and Flow is used for automating workflows—the Query tool is the most appropriate choice for the task of filtering contacts, as it's built specifically for data retrieval and filtering scenarios.

The option that includes all of the above suggests a broader capability, but in the context of filtering contacts directly, the Query tool is the most suited and efficient tool.