Answer:
4) he invented the bessemer process, he patented the telephone
Explanation:
Alexander Graham Bell was an American scientists that had big contribution in the industry and communication sectors. Some of his biggest contributions were the invention of the Bessemer process, which was revolutionary for the mass production of steel. This led to much higher quantities of steel to be produced, but also to be of higher quality, and to be produced quicker. Understandably, this led to big growth in the industry, as the steel was one of the most demanded construction materials. What made him famous though was the invention of the telephone. By inventing the telephone, Alexander Graham Bell managed to connect people on long distances without even seeing each other, or with other words he revolutionized the communication among the humans.