Scientists have found that although the wings of birds are not as stiff as those of airplanes, they are more able to adapt to different weather conditions, especially harsh weather conditions than airplanes, because the wings of birds can stretch freely, thus cleverly Adapted to changes in airflow. Inspired by nature, NASA scientists are working on a wing that can bend and deform. The design idea of this aircraft is to make the deformed wing of the aircraft slightly at high speeds. Rearward to reduce the resistance in flight and reduce the vibration caused by the airflow; when the aircraft slows down, the wings can automatically extend forward to help the aircraft land faster and more smoothly. It is not easy to deform the wing, the key is to use special intelligent materials to make this deformable wing, which can automatically flex and stretch after being exposed to external air pressure and stimulation. Among them, it is made of memory alloy. The wing material can change the aircraft wing into a special shape in a certain air environment; another important intelligent material is piezoelectric ceramics, which can A variety of environmental factors, such as voltage and temperature, respond sensitively. Scientists say that it will take at least 20 years for this type of aircraft with flexible wings to be successfully developed. By then, our aircraft will become more intelligent Comfortable and safe, flying freely in various environments like various birds. What is the most accurate restatement of the above paragraph? ['In the future, the aircraft will fly freely to various environments like various birds.', 'Bionics and intelligent materials science will help people better adapt to nature.', 'Bird wings are more adaptable to different weather conditions than aircraft wings.', 'The wing material made of memory alloy can change the aircraft wing into a special shape in a certain air environment.']