which of the following components of Microsoft Project Server architecture should these developers interact with rather than the project databases?

You work as a Project Administrator for Company Inc. You are working with some developers who want to create a third-party application to manipulate the Project Server business objects, such as the calendars in projects. You are concerned about maintaining data integrity, as the developers want to access the data in the Microsoft Project Server. To preserve data integrity, which of the following components of Microsoft Project Server architecture should these developers interact with rather than the project databases?

A.
Project Data Services

B.
Project Server Interface

C.
Project Server Queuing service

D.
Data Access Layer

Explanation:
Developers can access data of Microsoft Project Server by working with the Project Server Interface. This allows developers to take advantage of the ability of Microsoft Project Server to work with third-party application while preserving the data integrity of the project data. Answer option C is incorrect. The Project Server Queuing service works with the Project Server Information component, but this is not the best answer for the question. Answer option A is incorrect. Project Data Services was the mode of accessing data in past versions of Microsoft Project, but it has been replaced by the PSI in Microsoft Project Server 2010.
Answer option D is incorrect. The Data Access Layer is the architectural component that goes between the Application tier and the actual database.