An Air Bubble in a Vessel Can Be Prevented from Spreading

An air bubble in a vessel can be prevented from spreading to an adjacent vessel by:

A) air seeding.
B) transport upward in the transpiration stream.
C) movement of a torus away from an aperture of a bordered pit-pair.
D) the surface tension of the meniscus spanning the pores of the bordered pit-pair membrane.
E) the filtering effect of the roots.