Sana and Abha had 100 playing cards. Both of them lost 20 cards each. The product of the cards they now have is 900. Let A be the number of playing cards Abha started with. Which of the following quadratic equations does A satisfy?
A. A² + 100A + 2500 = 0
B. A² + 100A - 2500 = 0
C. A² - 100A + 2500 = 0
D. A² - 100A - 2500 = 0