单项选择题
（）is a technique used for illumination behind the liquid crystal display that makes LCDs easier to read.
A. Frontlight B. Backup Power C. Cathode ray tube D. Backlight
单项选择题 （）enables a computer processor to process two sets of instructions at the same time.
单项选择题 （）is commonly performed on CPUs and video cards to allow users to get enhanced performance.
单项选择题 Which of the following storage devices is not an example of an optical storage device?（）
