Why dont you apply for your immigration to Canada. If your immediate relations are there it should be much quicker.
well, because as she says, she wants to go there to study, not to live ;-)
Parisa, all you can do is reapply, and somehow make it very clear that you intend to go back to your country once you graduate. It's really silly, because if you're planning to stay abroad for 2, 3, 4 years, you don't know what you'll want to do after you complete your degree. But that's the game.
You tell them you'll go back home, and if they believe you, they'll let you go.
How did they find out that you had relatives in Canada? Did they ask about it?
Again, all you can do is reapply. If you own your home, you can use that. If you're married and your husband is staying in Iran, you can use that. If you have a job, you can ask your employer to write you a letter stating that the education you'll get in Canada is valuable. If your employer writes that you can have your job back when you graduate, so much the better.