How do you determine if a stock will be profitable for you?

I have a project for school in which I have to determine which of three stocks (DIS, BX, FUN) would be the most profitable or result in the least loss.
I’ve never really understood how this works, or what I would have to look at to determine that.
I don’t want the answer, but I just want to know how I would determine which of those stocks would be the most profitable.
What factors would I have to look at? Gross Profit, Net Income, stock prices?