Final answer:
The service offering a variety of databases like Tax Services, Primary Law Services, and Analytical Sources is called Tax Center, which is key for comprehensive tax-related research.
Step-by-step explanation:
The service that presents the practitioner with a wide variety of databases, including Tax Services, Primary Law Services, and Analytical Sources, is known as Tax Center.
This service offers a comprehensive collection of materials that range from detailed reports on varying topics such as health, social trends, and the economy, to full-text news articles, government publications, and financial data. Additionally, databases like can be used for scholarly literature searches across multiple disciplines, providing an expansive list of resources for further research.