Led by New York's Guggenheim, some museums are using web

Led by New York's Guggenheim, some museums are using web sites not as a complement to its museum galleries, but also as a stand-alone art resource, exhibiting exclusive pieces you cannot view at the museum.

Underlined for clarity.

(A) as a complement to its museum galleries, but also as a stand-alone art resource, exhibiting exclusive pieces you cannot view

(B) as a complement to their museum galleries, but also as a stand-alone art resource, to exhibit exclusive pieces you cannot view

(C) as a complement to its museum galleries, but as a stand-alone art resource, which exhibits exclusive pieces that cannot be viewed

(D) only as a complement to their museum galleries, but also as a stand-alone art resource, exhibiting exclusive pieces that cannot be viewed

(E) only as a complement to its museum galleries, but also as a stand-alone art resource, exhibiting exclusive pieces that are not on exhibit

Please explain.