题目

A new device (设备) works like a solar panel, except it doesn't harvest energy from the sun to produce electricity. Instead, it uses energy from the cold night sky.In the center of this device is a thermoelectric generator (热电发电机), which uses the temperature difference between Earth and outer space to create electricity.As long as one side of it is cooler than the other, the generator can produce electricity. The cooler side faces the sky and is attached to an aluminum plate. That plate is sealed under a transparent cover and surrounded with materials that keep heat out. It stays c下列属于渗透作用的是A.蚕豆在水中膨胀B.把萝卜放在盐水中变软C.把煮熟的马铃薯块茎放在清水中D.面粉吸水