Final answer:
Newfoundland and Labrador is the newest of Canada's 10 provinces, joining the Confederation in 1949.
Step-by-step explanation:
Newfoundland and Labrador is the correct answer to the question. It became the newest of Canada's 10 provinces by joining the Confederation in 1949. Sir John A. Macdonald, the first Prime Minister of Canada, played a pivotal role in the early formation of the country, though Newfoundland and Labrador joined much later than the original provinces of Nova Scotia, New Brunswick, and the Province of Canada, which included Ontario and Quebec, which were unified under the British North America Act of 1867. Over time, the confederation expanded, finally including Newfoundland and Labrador, which comprises two distinct parts: the island of Newfoundland and the mainland region of Labrador.