What were the most defining moments of the 20th century for Canada?

So the essay should be 4-5 pages long. Each body paragraph should include 3 points, proofs and explanation. AT the end of each proofs in the body paragraphs there should be a intext citation in MLA format. The work cited page should also be in MLA format. There should e at least 5 sources in the work cited page, At least one of them should be a book.