The author’s argument only addresses rehabilitation efforts among the otter population that was affected by the oil spill. Surely other otter species exist in other places, but their existence doesn’t call into question the evidence offered in support of the author’s conclusion.

This calls into question the author’s evidence. He claims that the percentage of successfully rehabilitated otters is much lower than 18% because only a fifth of the dead otters were ever found. But how can he know that this number is accurate if the otters were never found?

Like (A), the author’s argument is only concerned with those otters that were affected by the spill. The effects of the rehabilitation process on other otters doesn’t call into question his evidence, which only addresses affected otters.

The author’s evidence only addresses sea otters that were affected by the oil spill. Whether other species of wildlife were also affected is irrelevant, since the rehabilitation efforts in question only involved sea otters.

The author doesn’t mention cost as a factor in his assessment of whether the rehabilitation effort was worthwhile. (E) thus doesn’t call into question the author’s evidence, which only addresses the percentage of otters that were rehabilitated.