Nhận biết (M1)

Some glass products contain aluminum oxide nanoparticles (Al₂O₃ -NPs), which can leach into waterways and soils via wastewater. In a 2010 study, Jacob K. Stanley and colleagues found that Al₂O₃-NPs can accumulate in the bodies of Asian clams (Corbicula fluminea). While bioaccumulation of manufactured nanoparticles may be inherently worrisome, it has been hypothesized that Al₂O₃-NP bioaccumulation in invertebrates like C. fluminea could serve a valuable proxy role, obviating the need for manufacturers to conduct costly and intrusive sampling of vertebrate species—such as Chinook salmon (Oncorhynchus tshawytscha), commonly used in regulatory compliance testing—for nanoparticle bioaccumulation, as environmental protection laws currently require.

Which finding, if true, would most directly weaken the hypothesis presented in the text?

• A.

  Al₂O₃ - NP concentrations in C. fluminea show no reliable correlation with Al₂O₃-NP concentrations in O. tshawytscha when the two species are exposed to similar levels of Al₂O₃- NPs

• B.

  C. fluminea has been shown to accumulate several other types of manufactured nanoparticles in addition to Al₂O₃- NPs, whereas O. tshawytscha has been shown to accumulate only Al₂O₃-NPs.

• C.

  Given comparable levels of exposure to Al₂O₃-NPs, C. fluminea accumulates Al₂O₃-NPs at a higher rate than O. tshawytscha does but in a fixed ratio to the rate at which O. tshawytscha does.

• D.

  Compared with O. tshawytscha, C. fluminea can accumulate detectable Al₂O₃-NP concentrations with significantly fewer negative effects.