Final answer:
George and Wanda's total dividend income is $33,600, which is part of the investment return from stocks owned by George.
Step-by-step explanation:
The total dividend income received by George and Wanda, who file a married joint tax return, is $33,600. This income comes from stocks owned by George. Dividend income is a form of investment return that companies distribute to their shareholders from the profits earned. This contrasts with capital gains, which are realized when an investment is sold for more than its purchase price.