Concerning the recent proliferation of free music available on the internet, record companies have devised strategies to reclaim their lost revenue.
A. Concerning the recent proliferation of free music available on the internet, record companies have devised B. Concerning the recent proliferation of free music available on the internet, record companies are devising C. Concerned with the recent proliferation of free music available on the internet, record companies are devising D. Concerned over the recent proliferation of free music available on the internet, record companies had devised E. Concerning the free music proliferating on the internet recently, record companies devised