Which of these was the least important aspect of imperialism in the period following european industrialization?

 The global expansion of western Europe between the 1760s and the 1870s differed in several important ways from the expansionism and colonialism of previous centuries. Along with the rise of the Industrial Revolution, which economic historians generally trace to the 1760s, and the continuing spread of industrialization in the empire-building countries came a shift in the strategy of trade with the colonial world. Instead of being primarily buyers of colonial products (and frequently under strain to offer sufficient salable goods to balance the exchange), as in the past, the industrializing nations increasingly became sellers in search of markets for the growing volume of their machine-produced goods. Furthermore, over the years there occurred a decided shift in the composition of demand for goods produced in the colonial areas. Spices, sugar, and slaves became relatively less important with the advance of industrialization, concomitant with a rising demand for raw materials for industry (e.g., cotton, wool, vegetable oils, jute, dyestuffs) and food for the swelling industrial areas (wheat, tea, coffee, cocoa, meat, butter).

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could you go a bit more in depth with you question? it's quite hard to understand. as soon as you do that i will be glad to : )