In the Wealth of Nations, Adam Smith Wrote

In the Wealth of Nations, Adam Smith wrote:
Pecuniary wages and profit, indeed, are everywhere in Europe extremely different according to the different employments of labour and stock. But this difference arises partly from certain circumstances in the employments themselves, which, either really, or at least in the imaginations of men, make up for a small pecuniary gain in some, and counterbalance a great one in others; and partly from the policy of Europe, which nowhere leaves things at perfect liberty. (Book 1, Chapter 10)
Which idea was Smith describing?

A) labor market issues
B) market discrimination
C) supply of labor
D) marginal product of labor