单选题 Which of the hypothetical discoveries would MOST likely shed doubt on the author's claim that "field regeneration" could be responsible for the earth's magnetic reversals?

• (A) Extreme fluctuations in the dynamo processes are discovered to be exceedingly rare, if they occur at all.
• (B) Magnetic field lines are discovered to diffuse very poorly through the earth's outer core.
• (C) Realignment of the earth's magnetic polarity is discovered to occur much more frequently than was previously believed.
• (D) Molten iron is discovered to be a poorer electrical conductor than was previously believed.
• (E) The earth's core is found to move at a much faster rate than had previously been measured.