Home » Transmission lines » 20 » b If an antenna feedline must pass near grounded metal objects, the following type should be used:   a.   75 ohm twinlead   b.   300 ohm twinlead   c.   600 ohm open-wire   d.   coaxial cable Your answer "b" is not correct. "d" is the right answer. That was the last question for this topic.