Artiﬁcially delivering biomolecules to plant cells is an important component of protecting plants from pathogens, but it is
diﬃcult to transmit biomolecules through the layers of the plant cell wall. Markita del Carpio Landry and her colleagues have
shown that it may be possible to ______ this problem by transmitting molecules through carbon nanotubes, which can cross
cell walls.
conceptualize
neglect
illustrate
overcome
Choice D is the best answer because it most logically completes the text’s discussion of delivering biomolecules to plant
cells. In this context, “overcome” means to succeed in dealing with an obstacle. The text suggests that although it’s diﬃcult
to move biomolecules through plant cell walls, Landry and her colleagues have shown that carbon nanotubes may be useful,
since they can cross cell walls. This context conveys that Landry and her colleagues think it’s possible, using carbon
nanotubes, to succeed in dealing with the obstacle of transmitting biomolecules to plant cells.
Choice A is incorrect because it wouldn’t make sense in context to say that Landry and her colleagues have shown that it
may be possible to “conceptualize,” or form an idea of, the diﬃculty of transmitting biomolecules through the walls of plant
cells. The text presents this diﬃculty as a known problem that Landry and her colleagues think they may have solved, not as
a mysterious occurrence that they have yet to form ideas about. Choice B is incorrect because the text suggests that Landry
and her colleagues think it may be possible to successfully deal with the problem of transmitting biomolecules through the
walls of plant cells, not that Landry and her colleagues think it may be possible to “neglect,” or simply to disregard and ignore
the problem. Choice C is incorrect because it wouldn’t make sense in context to say that Landry and her colleagues have
shown that it may be possible to “illustrate,” or demonstrate, the diﬃculty of transmitting biomolecules through the walls of
plant cells by using carbon nanotubes. According to the text, carbon nanotubes allow molecules to be transmitted to plant
cells—something that is otherwise diﬃcult to do. The text therefore presents carbon nanotubes as a way of possibly solving
a problem, not as a means of demonstrating the problem.