Using indifference curve analysis, illustrate the difference between the two following explanations of the increasing share of coffee in the market for beverages in the last few decades. (a)...

Using indifference curve analysis, illustrate the difference between the two following explanations of the increasing share of coffee in the market for beverages in the last few decades.

(a) 'Consumer preferences have not changed. The share of coffee has risen because incomes have risen and tea is an inferior good.'

(b) 'Consumer tastes have changed, wiThthe help of marketing. If they hadn't then tea and coffee would still have unchanged market shares despite the rise in incomes.'