The correct answer is option 1, John Locke. John Locke, a prominent philosopher and political theorist, argued that Democracy is a system of government based on the consent of the governed. He believed that the legitimacy of a government depends on the voluntary agreement and consent of the people being governed. According to Locke, power should not be derived from divine right or force, but from the people themselves. He advocated for individual rights and limited government, and his ideas heavily influenced the development of democratic principles.

Option 2, J.S. Mill, was also a philosopher and political economist. While he contributed significantly to the theory of democracy, he did not explicitly state that democracy means government by consent.

Option 3, Jeremy Bentham, was a philosopher and legal theorist who proposed the concept of utilitarianism. While he wrote extensively on the principles of good governance and the importance of the consent of the governed, he did not directly link democracy to government by consent.

Option 4, J.J. Rousseau, was a philosopher who wrote about the social contract theory. While he argued that legitimate political authority should be based on the consent of the people, he did not specifically define democracy as government by consent.

In conclusion, John Locke is the correct answer as he explicitly stated