Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions. T...

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

The concept of a personal flying drone for everyday commuting is gaining traction, although experts acknowledge it may be decades before it becomes a reality.

Most current drones operate differently than a piloted aircraft, relying on GPS navigation and advanced algorithms to control flight paths. This approach is more efficient and simpler than having a human pilot, but it is also limited by current battery technology and air traffic regulations.

A team at the Aeronautics Institute of Technology has developed a prototype personal drone, called "Skyhopper," designed to carry a single passenger. It features an advanced propulsion system and a lightweight composite frame, along with sensors for obstacle avoidance and autonomous flight control. Artificial intelligence systems determine the necessary flight maneuvers and respond to real-time changes in weather and air traffic. The drone can currently perform a limited range of flight tasks, such as vertical takeoff and landing, hovering, and short-distance travel at low altitudes in controlled environments. "The speed and range are not yet comparable to traditional aircraft," says lead engineer Dr. Anya Sharma.

It appears that a personal drone capable of navigating complex urban environments and ensuring passenger safety is still far from being commercially available. As mentioned previously, it could be many years before such a device becomes commonplace.

However, the potential benefits of personal drones are significant. They could reduce traffic congestion, provide faster and more efficient transportation, and open up access to remote areas. Ongoing research focuses on improving battery life, developing robust safety systems, and establishing clear regulatory frameworks.

The future of personal drones hinges on overcoming technical challenges and gaining public acceptance. With continued innovation and careful planning, the dream of personal flight may one day become a reality.

Trả lời cho các câu 636, 637, 638, 639, 640 dưới đây:

Câu 636: What does "it" in paragraph 2 refer to?

A. A drone
B. This method
C. The GPS system
D. Battery technology