You are not entitled to an A, B or C-.
What you are entitled to, however, is a fair assessment of your work and the corresponding grade.
You pay several hundred dollars for each course you take, plus the assortment of fees that push your tuition costs higher every year. In Canada, the taxes paid by you, your family members, and the people of Canada cover much of the cost of running the university you attend and comprise the research budgets of many of your professors. These tax dollars also pay the wages of the graduate students who quite often are the ones assessing your work.
You have more than enough grounds to openly question the method and rationale behind any assessment you receive. You and the rest of the country have paid for it.
You might find out, for example, that the
More to the point, this means that you did not get the full suite of detailed comments and grading notes that that were potentially available for your work. In other words, your work was not as rigorously assessed as it could have been. Some of you benefit from this because your mark is higher than it could have been, and some of you suffered because your mark is lower than it could have been. In either case, you were screwed, and so was your assessor.
And that is something you can line up in front of your professor's door and clog their inbox about.
You're entitled to it.