Critical Reasoning

The Rienzi, a passenger ship, sank as a result of a hole in its hull, possibly caused by sabotage. Normally when a holed ship sinks as rapidly as the Rienzi did, water does not enter the ship quickly enough for the ship to be fully flooded when it reaches the ocean floor. Full flooding can be achieved, however, by sabotage. Any ship that sinks deep into the ocean when not fully flooded will implode. Deep-sea photographs of the Rienzi where it rests on the ocean floor, reveal that it did not implode.

Which one of the following must be true on the basis of the information above?

A) The Rienzi was so constructed as to reduce the risk of sinking by impact.

B) If the Rienzi became fully flooded, it did so only after it reached the ocean floor.

C) If the Rienzi was not sunk by sabotage, water flooded into it unusually fast.

D) If the Rienzi had sunk more slowly it would have imploded.

E) The Rienzi was so strongly constructed as to resist imploding under deep-sea pressure.

Please explain you choice.