I think its C. they staged a counter-demonstration. I may be wrong.
<span>Guglielmo Marconi's work was in radio signals, and one of his inventions was the radio telegraph (AKA wireless telegraph)</span>
The phenomenon of logrolling occurs when two members of congress conflicts in their interests, however, support each other's bills. Furthermore, the principle is commonly used in the Congress and is named to a sport. It is also called "trading of favours" or "quid pro quo."