∴BG=4,AG=2

∴S△AGB=4

∵S right angle AEOC=S right angle OFBD, and the area of quadrilateral FOCG is 2.

∴S rectangle AEOC=S rectangle OFBD= 12(S pentagon aeodb-s △ ag-s quadrilateral FOCG)+S quadrilateral focg =12 (14-2)+2 = 6.

That is k=AE? AC=6。

So choose C.