Identify the Reasons Why the Quantity Demanded of a Product

Identify the reasons why the quantity demanded of a product increases as the price of that product decreases.

A) as the price declines,the real income of the consumer increases
B) as the price of product A declines,it makes it more attractive than product B
C) as the price declines,the consumer will always demand more on each successive price reduction
D) a and b
E) a and c