Are you in school?
It used to be common foods would be regionalized, but in the age of global big food that is less so. This is an important point, because the nutritional value of some foods varies by the soil in which it is grown, and of course while organic and non organic may have similar nutritional profiles they differ in significant toxicities for some foods. And of course whole foods are generally more nutritionally healthy than processed stuff even when lots of money is spent to convince us with ads on the boxes about how nutritionally wonderful the stuff is.
So I would say: bananas for potassium, and black beans for fiber, and avocados which have over a dozen nutrients in them.
Is this a quiz? I love quizzes. Here we go. – yogurt/calcium, carrots/vitamin A, strawberries/vitamin C.