Directions: After reading the following passage, you will find 5 questions or unfinished statements, numbered 36 through 40. For each question or statement there are 4 choices marked A, B, C, and D. You should make the correct choice.
Radio signals for the next generation of mobile phone services can cause headaches.
A study was carried out recently by the Dutch Technological Research Institute. The study was the first to look for the impact of mobile phones on health. It was als
According to the passage, compared to 3G mobile phones, the second-generation phones ______.
A.do not receive signals transmitted with an electromagnetic field
B.can receive signals from a larger area than 3G mobile phone
C.cause worse impact when they are used close to the head
D.have no negative impact on human health