A. add the areas of both bases to the rectangular area around the cylinder.
Step-by-step explanation:
If we flatten out the cylinder we would have two circles and a rectangle. When you roll up the rectangle, it would make the body of the cylinder. Surface area by definition the total area the surface of an object occupies.
So to get it, we add up the different shapes that make up the cylinder, which is the two circles and the rolled up rectangle.
