题目

阅读理解It seems that electronic devices just keep getting smaller. Scientistsin the United States have announced the creation of the first transistor withonly two dimensions(二维).A transistor is a small electronic device that transfers or carrieselectronic current. Scientists hope these new 2D transistors will be used forbuilding high-resolution(高分辨率)displays that need verylittle energy.Two groups of scientists created these 2D transistors. They report thatthe transistors are only a few atoms thick.Usually transistors are made with the element silicon(硅). Computer processors,质量相同的下列金属，分别加入到足量的稀盐酸中充分反应，放出氢气最多的是(    )A．MgB．AlC．CuD．Zn