Concept:
Brihadeshvara Temple at Tanjavur is one of the greatest temples of the Chola period. It is also known as Rajarajeshwaram and is dedicated to Lord Shiva.
Step 1: Check statement A.
The temple was constructed by Rajaraja Chola I.
So, statement A is correct.
Step 2: Check statement B.
The temple is famous for its very tall vimana.
So, statement B is correct.
Step 3: Check statement C.
The statement about the largest cantilever beam is not a standard identifying fact of Brihadeshvara Temple.
So, statement C is incorrect.
Step 4: Check statement D.
The temple is dedicated to Lord Shiva, not Lord Hari.
So, statement D is incorrect.
Step 5: Check statement E.
The temple is not known for construction in buff sandstone.
So, statement E is incorrect.
Thus, the correct statements are:
\[
A,\ B
\]
Hence, the correct answer is:
\[
\boxed{\text{(A) A and B only}}
\]