Alittleunderamillionyearsago,thebrinywatersoftheBalticSeabeganfloodingintothecoldNorthAtlantic:geologistsarestilldebatingwhetherthefloodwasgradualorcreatedacataclysm.（）
(A)whetherthefloodwasgradualorcreatedacataclysm
(B)ifthefloodwasgradualorcreatedacataclysm
(C)aboutwhetherthefloodwasgradualorcataclysmic
(D)whetherthefloodwasgradualorcataclysmic
(E)whetherthefloodwasgradualoritcreatedacataclysm