Colonial officials were strongly influenced by the ideas of which British economic thinker in 19th-century ?

David Ricardo

The correct answer is Option (3) → David Ricardo

Comparative Advantage and Free Trade: David Ricardo is best known for his theory of comparative advantage, which argues that countries should specialize in producing goods in which they have a relative efficiency or advantage and engage in international trade based on these advantages.

Economic Liberalism: Ricardo's ideas aligned with the broader economic liberalism that was prevalent in 19th-century Britain. Economic liberalism emphasized limited government intervention in economic affairs, the removal of trade barriers, and the promotion of laissez-faire economic policies.

Colonial Trade and Resources: Many colonies were seen as sources of valuable resources and markets for British goods. Ricardo's ideas supported the notion that removing trade restrictions and allowing colonies to specialize in what they could produce most efficiently would benefit both the colonies and the British Empire.

British Imperialism: Ricardo's ideas were in line with the broader goals of British imperialism, which sought to maximize economic benefits and the flow of goods within the British Empire.

So, the correct option is [3].