Plz help The telephone
Bell kept working on the telephone. On March 10 of the same year, Bell and Watson made the telephone work. Bell and Watson then improved the telephone. In August 1876, Bell sent a telegram to a town five miles away. People in the telegraph office could hear voices on the telephone. The next day, Bell strung a telephone wire across six miles. The message sent over the telephone wire could be heard clearly. This showed that the telephone worked over long distances.

Which detail from the third paragraph is most important to include in a summary of the passage?
A.
Bell's telephone used wires to transmit voices.
B.
Bell sent a telegram to a town five miles away.
C.
Bell and Watson made the telephone work.
D.
Bell sent his telegram from a telegraph office.