A. All levels of demand, whether individual, aggregate, local, national or international are subject to change.
B. At the same time, science and technology add new dimensions to products, their uses, and the methods used to market them.
C. Aggregate demand fluctuates with changes in the level of business activity, GNP, and national income.
D. The demands of individuals tend to vary with changing needs and rising income.
Genre- Business/Economy
One thing which is clear here is that B comes at the end because it talks about science and technology, while the rest of the sentences talk about demand. So, we are left with options (b) and (d).
A is the first sentence because it introduces changes in demand. Hence, (d) is the answer.
CAT 1993