题目内容：

Over a decade ago, scientists already recognized the potential smart cloths with sensors (传感器) could improve well-being. Nowadays the industry is starting to target specific health conditions. One example is diabetes. Now, Siren Care has developed an injury-detecting sock that could help people with diabetes prevent disability. Early detection is important in this process. Since skin ulcers (溃疡) are accompanied by a rise in temperature, studies show that detecting foot skin temperature at home could significantly reduce skin ulcers. Based on this, Siren produced a sock that can measure foot temperature in real time.

What’s special about Siren’s product is that the sensors exist in the fabric of the sock. The product is powered by “SirenSmart”, a kind of electronic yarn (纱线). They weave the yarn into a sock using ordinary weaving machines and connect the final product to a PCB battery, whose lifetime is two months if used daily. The socks are only on when they’re worn; they go into sleep mode when off.

All data from the socks is sent to the Siren app using Bluetooth technology, so the user can know the condition of his/her feet in real time. The application gives foot health scores and, when necessary, warns the user to adjust activity or see a healthcare professional.

Ran Ma, the company’s CEO, explains the sock can tell the user when to see a doctor. The socks are machine-washable, and don’t need to be charged. Every six months, the user gets a new box with seven pairs of socks to replace the used ones.

Siren presented their product this year in Las Vegas and announced that they’re planning to start shipping their socks this summer. More excitingly, Siren is already planning future applications that will go beyond diabetes care. Anyway, as smart clothing becomes accessible, you’ll begin to see this health technology become more common.

1.What does the underlined word “this” in Paragraph 1 refer to?

A. The result of the study.    B. The problem with skins.

C. The cause of skin ulcers.    D. The importance of early detection.

2.What can we learn about Siren’s smart sock from the second paragraph?

A. It can be charged.    B. It is sensitive to skins.

C. Its sensors can be seen.    D. It is comfortable to wear.

3.What should be the function of the smart sock?

A. It cures its user of possible illness.

B. It informs its user of his/her foot health.

C. It assists its user to make a quicker recovery.

D. It tests its user’s physical strength in real time.

4.What does the author think of the smart clothing industry?

A. It has a bright future.    B. It is a profitable industry.

C. It is readily available.    D. It has widely applied.