Too simple apple muffins

My friends told me these ones are the best:


Ingridients:
1 1/2 cups all-purpose flour
1/2 cup sugar
2 teaspoons baking powder
1 teaspoon ground cinnamon
1/2 teaspoon salt
1 egg
1/2 cup milk
1/4 cup oil
2 cup chopped, peeled tart apple