Explanation
A. Even if the habitat could support a larger population, this does not address the concern that the building site will reduce the current habitat area.
B. (Correct Response) If the dolphins do not inhabit water that is less than 10 meters deep, then the land that is only 5 meters deep, which is planned for the building site, would not be part of their habitat. Therefore, creating a building site there would not reduce the habitat area actually used by the dolphins.
C. While this may or may not be true, it does address the criticism concerning the reduction of habitat area due to the building plan.
D. The average depth of water does not refute the critics' concern about the reduction in habitat area.
E. The depth of the ocean floor adjacent to the habitat does not counter the argument about the building site's impact on the shallow water habitat.
The statement that most logically completes the argument and refutes the critics is option B, because it clarifies that the building site's depth does not encroach upon the dolphins' usable habitat area. If dolphins do not use areas that are less than 10 meters deep, then a construction site at 5 meters depth would not affect their habitat.