How Did the Residents of Vestmannaeyjar,Iceland,save Their Harbor from a Lava

How did the residents of Vestmannaeyjar,Iceland,save their harbor from a lava flow?

A) They dug channels that diverted the lava flow away from the harbor.
B) They extracted more geothermal energy that was being produced by the volcano, decreasing the volume of lava erupted.
C) They constructed high cement walls around the harbor and the lava solidified against the walls.
D) As the lava cooled, they blasted the new rock away and dumped it offshore.
E) They chilled the lava flow with water, making the flow solidify before it blocked the harbor.