Which of the Following Is One Explanation as to Why

Which of the following is one explanation as to why the aggregate demand curve slopes downward?

A) Decreases in the price level raise the interest rate and increase consumption spending.
B) Decreases in the price level raise the interest rate and increase investment spending.
C) Decreases in the Canada price level relative to the price level in other countries lower net exports.
D) Decreases in the price level raise real wealth and increase consumption spending.
E) Decreases in the price level raise the value of the multiplier.