Ad hoc reports multiple tables

HI,
i am a new to SSRS and i am facing a problem with Ad Hoc reporting.
actually i wanted to create a report with data from two different table. now its the relation between these two tables that is not allowing me to create a req. adhoc report.

i want the report to have data from table A and table B and the relationship between A and B is many-to-many. so in the database design i have an associate table C between A and B. so in .dsv file i have C related to A as one-to-many and C related to B as one to many.

Now here how do i get data from both table A and table B?
i will put some more info, put the question in a different way.

Say I have 3 tables related as shown in the diagram below

Say

1) plan organization

2) plan

3) plan opportunity

in the ad hoc report I wanted to have data from plan organization and plan opportunity.

How will I do that?

plan organization >-|- Plan -|--< plan opportunity

one-to-many relation between plan and plan organization
one-to-many relation betweeb plan and plan opportunity