Investigation: What design makes the best parachute?

The Dolphins worked in teams to make their own parachutes in order to safely drop an egg. We learned that the parachute’s surface area affects its air resistance, or drag force. In the case of these parachutes, the drag force is opposite to the force of gravity, so the drag force slows the parachutes down as they fall. Which parachute design gives the most effective surface area?