Sentence Correction

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

[spoiler]OA: After some discussion. Please explain each answer choice in detail.[/spoiler]

i hope that choices here only between C and D

D is out as it violates ||-ism
that would rise and.....act, absorbing ... and protecting....is good in C
C to me

yup I got it ........the answer is C only