Answer:
Because he heard a patient’s yelp through a copper wire, Antonio Meucci invented the “talking telegraph.”
Explanation:
A cause-and-effect relationship is a relationship where one event causes another to happen. The first event is referred to as the cause and its result is referred to as the effect.
Here, we have Antonio Meucci, a trained engineer who created the <em>talking telegraph</em> after hearing a patient's yelp through a copper wire. His engineering knowledge was necessary for this invention, but it isn't the cause. If he hadn't heard the patient's voice through the wire, he probably wouldn't have thought of the talking telegraph.
This is the fourth option is the correct one.
