Which of the Following Events Is Most Likely to Directly

Multiple Choice

Which of the following events is most likely to directly cause a meltdown in a nuclear fission reactor?

A) The fuel rods become old and brittle.
B) The reactor is operated at too high a power.
C) The chain reaction slowly starts to get out of control.
D) Pumps that circulate water in the reactor fail.
E) Either B or C.