The answer choice D "Friction and turbulence near the boundary between the outer core and the mantle are typically caused by asteroid impacts" is incorrect for several reasons. The passage states that the impact of an asteroid large enough may cause redistribution of the seawater, which in turn causes friction and turbulence near the outer core-mantle boundary. We can neither conclude that the friction and turbulence cannot result from another force aside from redistribution of the seawater nor that redistribution of seawater cannot be caused by something other than the asteroid impact. In other words, we do not have enough information to say that friction and turbulence are TYPICALLY caused by asteroid impacts though the asteroid-impact hypothesis in the passage suggests that it may happen with an asteroid large enough.
