According to the article, which of the sentence can best describe the definition of the telecommunication
A．Telecommunications are devices and systems that transmit electronic signals across long distances.
B．Telecommunications allows people around the world to contact one another, to access information instantly, and to communicate from remote areas.
C．Telecommunications usually involves a sender of information and one or more recipients(收件人) linked by a technology.
D．Telecommunications are devices and systems that carry, electronic signals across short distances.