James Watt: Identify the invention most associated with his name in industrial history. Full question: What did James Watt invent (in common GK usage)? Choose the correct option.

Given data

• Topic: Industrial Revolution era inventions.
• Person: James Watt.

Concept / Note
Historically, Watt is credited in common-general-knowledge with the steam engine. Technically, he greatly improved the Newcomen engine by adding a separate condenser, transforming efficiency and enabling broad industrial use.

Option analysis
Steam engine (improved): Correct in GK framing. Electric motor: Pioneered by inventors like Thomas Davenport and others. Jet engine: Frank Whittle and others, 20th century. Telegraph: Samuel Morse and others.

Final Answer
Steam engine (improved with separate condenser).