Which sentence is punctuated correctly?

A. Before you leave for the store . . . check to make sure your grocery list is complete.
B. Because, we live at a high elevation, sometimes we have to adjust the cooking time for recipes.
C. I added bread, milk and sugar to the list of ingredients needed to make the recipe.
D.Baking bread is one of my favorite things to do- on a weekend afternoon.

C. I added bread, milk and sugar to the list of ingredients needed to make the recipe.