$[$Related to Making the Connection$]$ A column in the Wall Street Journal, asks the question: "Are capital gains so different from earned income that they should be taxed at a different rate?"

Source: Scott Sumner and Leonard E$.$ Burman, $"$Is It Fair to Tax Capital Gains at Lower Rates Than Earned Income?" Wall Street Journal, March $1,2015.$

What is a capital gain?

A$.$ The increase in capital from one year to the next.

B$.$ A distribution of profit to investors.

C$.$ An increase in the price of a stock.

D$.$ A profit from the sale of an investment.