Which of the Following Is True

Which of the following is true?

A) The long-run aggregate supply curve slopes upward to the right.
B) The aggregate quantity demanded of goods and services slopes downward to the right because it is simply the sum of the demand curves for each individual product.
C) An unanticipated increase in demand will increase prices and improve profit margins in the goods and services market,leading firms to expand output.
D) An anticipated increase in demand will lead to higher resource prices,which will cause firms to expand their output.