Which choice most logically completes the text? | Verbal SAT Question

Research such as the 2012 study of mammals by Soledad Lucía Uran and colleagues has shown that noise from human activity, like traffic on a busy highway, has significant effects on animals, and many governments require studies of the potential noise effects on wildlife before approving highway construction projects. Advocates for one such project in an area home to both mammals and birds argue that since previous research has shown that birds are, on average, less affected by such noise than mammals are, the effect of the proposed project on birds does not need to be studied. Conservationists counter that basing such a decision on average effects is problematic because

Which choice most logically completes the text?

the effects of noise on birds have been more extensively documented than the effects on mammals have.

the average for the effect of noise on birds is based on a much larger number of distinct species than the average for the effect of noise on mammals is.

addressing the effects of noise on birds is likely to help mitigate some of the effects on mammals.

the severity of the effect of noise on some species of birds could be much higher than the average effect.