GMAT Sentence Correction (SC) | Re: In a plan to stop the erosion of East Coast beaches, the

In a plan to stop the erosion of East Coast beaches, the Army Corps of Engineers proposed building parallel to shore a breakwater of rocks that would rise six feet above the waterline and act as a buffer, so that it absorbs the energy of crashing waves and protecting the beaches.
(A) act as a buffer, so that it absorbs
(B) act like a buffer so as to absorb
(C) act as a buffer, absorbing
(D) acting as a buffer, absorbing
(E) acting like a buffer, absorb