Final answer:
New Brunswick is joined by land to Quebec and Nova Scotia. These connections make up part of the Canadian Maritimes, and while Prince Edward Island is nearby, it is not connected by land.
Step-by-step explanation:
The provinces joined to New Brunswick by land are Quebec and Nova Scotia. These provinces make up part of the eastern region of Canada known as the Maritimes. New Brunswick shares its western border with Quebec and is connected to Nova Scotia by the Isthmus of Chignecto.
While Prince Edward Island is close geographically to New Brunswick, it is not connected by land; instead, it is accessible by the Confederation Bridge or by ferry. To answer the student's question directly, option (d) Quebec and Nova Scotia are the provinces joined to New Brunswick by land.