The author mentions 'other areas near the North Sea' primarily in order to

While the author does reference other areas near the North Sea, this mention is not to introduce a new hypothesis. Instead, it serves to question the existing explanation rather than suggest an alternative theory. Proposing a new hypothesis would require a different approach, focusing on establishing a new understanding rather than critiquing an existing one.

Anticipating a possible objection involves predicting counterarguments that may arise, which is not the primary purpose of mentioning other areas. The author's focus is on demonstrating the weaknesses of the current explanation rather than preparing for dissenting views. This choice misinterprets the author's intent to critique rather than defend.

While ambiguity can be a part of the discussion, the author's reference to other areas does not primarily aim to highlight vague or unclear aspects of the argument. Instead, it seeks to provide concrete examples that challenge the robustness of the explanation, focusing more on doubt than ambiguity.