Pls help!!!! It’s for economics!!!

Which of the following illustrates a capital gain? (1 point)
A. An investor purchases a stock for $25 and then later sells it for $30.
B. An investor purchase a stock for $30 and then later sells it for $25.
C. An investor earns a $20 return from a savings deposit.
D. An investor earns a $20 return from a bond held until maturity.