单项选择题
A．measures the movements of a spaceship by means of light beam B．makes use of microwaves C．makes use of sound waves D．Both A and B
A．was interested in flowers and insects in his childhood B．lost his hearing when he was a child C．didn’t like his brothers and sisters D．was born to a naturalist’s family
A．through great social revolution B．through automotive technological revolution C．through numerous mechanical inventions D．through radical political reforms