Need help please. It's urgentabout recount the main topic.. Thank you. A View from the Clouds-
Written by Elizabeth Baker with Laura Kachelmeyer

Have you ever looked out your window and seen clouds all around you? You must have been up in an airplane! Airplanes make traveling and shipping very easy and fast, but we didn’t always have the ability to fly. It has taken humans a long time to understand how to create the complicated structure known as the airplane.

Humans have dreamed of soaring through the clouds for centuries. Even people in Ancient Greece and China tried to invent ways for people to fly in the sky thousands of years ago. It wasn't until the 1900s that more modern airplanes like those we use today were invented. Many engineers and designers, like the Wright brothers, spent years testing different kinds of airplane engines, wings, and controls. They finally figured out how to make airplanes fly through the air!

Airplanes can fly because they generate a force called lift. Lift begins to happen when the airplane’s engines roar into life. The strong engines push the airplane forward. The wheels on the plane help it move faster. As the plane's engines push the wings forward, air moves over and under them. The air moving under the wings is strong enough to hold the plane up. If you cut a slice across an airplane wing, you see it is curved over the top and flat on the bottom. This difference creates a stronger force of air underneath the wing, which pushes it upward.
Since The early 1900s, engineers have designed planes to be used in wars, for shipping goods, and to help people travel long distances in less time. Today, over 100,000 planes take flight around the world. That means that there are thousands of people soaring through the clouds at this very moment!

Based on the first paragraph, how can you recount the main topic of this text?
a) Airplanes make traveling and shipping very easy and fast, but we didn’t always have the ability to fly
b) The airplane took many years to construct because it was hard to make something fly.
c) The airplane is simple and fairly new.
d) It has taken humans a long time to understand how to create the complicated structure known as the airplane.