Explanation:

- Option 1: 19th Century

- The modern Iron and Steel industries began in the 19th century. This was due to the Industrial Revolution, which introduced new techniques like the Bessemer process.

- Option 2: 17th Century

- There were early uses of iron and small-scale ironworks, but not organized industries as we know today.

- Option 3: 20th Century

- The steel industry expanded globally in the 20th century, but it did not begin then. It was already well established.

- Option 4: 14th Century

- In the 14th century, iron was used, but industrial-scale production did not exist.