No matter how frequently ________, the works of Beethoven still attract people all over the world.

1. A.
   performed
2. B.
   performing
3. C.
   to be performed
4. D.
   being performed

No matter how frequently _______, the works of Beethoven still attract people all over the world.

   A. performed   B. performing   c. to be performed   D. being performed

No matter how frequently ______,the works of Beethoven still attract people all over the world.

A.performed                        B.performing

C.to be performed                D.being performed

No matter how frequently __________, the works of Beethoven still attract people all over the world.

A. performed  B. performing

C. to be performed D. being performed

No matter how frequently __________, the works of Beethoven still attract people all over the world.

A. performed????????????? B. performing

C. to be performed????????????? D. being performed