阅读下列短文，从每题所给的 A、B、C、D 四个选项中选出最佳选项。
A
Some inventions are so common that it’s difficult to imagine they started as an idea written on paperand then a patent application submitted to the U.S. Patent and Trademark Office (USPTO). The ballpointpen, the computer mouse, and the microwave oven-these are just a few examples of great ideas that becameessential products we now take for granted.
Nevertheless, of the 520,277 applications that inventors filed with USPTO in 2010, chances are thatnot even half will be granted patents, and far fewer will become commercial successes. In that spirit, hereare three of the technological advances:
Mind Control Helmet
The helmet is equipped with the trans cranial pulsed ultrasound(经颅脉冲超声) technology, whichdelivers high-frequency sound waves to specific regions of the brain. Under the influence of these soundwaves, neurons(神经元) send impulses(脉冲) to their targets, taking control over them.
Body Armor with Flashlight and Camera/Phone Charger
The flexible arm, which is armored with Kevlar and hard plastic, contains a rechargeable battery packthat powers a special device built into the arm's artificial skin. It is also equipped with a bright LEDflashlight, an HD camera capable of sending pictures, and a charging slot into which a phone apparently fitsnicely.
Robot That Eats Mice and Insects
The robot would chase and eat mice and insects, and then digest their bodies to produce its own power.There are five different concepts, including the mousetrap coffee table robot, which is designed to attractcareless insects onto its surface, which contains a trap door set off by motion sensors. Victims trapped bythe device would be chemically separated and fed to a microbial fuel cell. A light on the side of the devicewould inform the owner of how much energy is being produced.
These inventions push the boundaries of innovation, yet they seem unlikely to gain widespreadacceptance.
21. How many applications do you think will become commercial successes?
A. 520,277 B. 260,138 C. 250,638 D. 120,220
22. What does the underlined word "slot"in Paragraph 4 probably mean?
A. computer B. pocket C. switch D. opening
23. What is the author’s attitude towards these three inventions?
A. favorable B. indifferent C. doubtful D. objective
