A. Original Price = Discounted Price × (100 ÷ (100 – Discount Percentage))
B. Original Price = Discounted Price × (100 ÷ Discount Percentage)
C. Original Price = Discounted Price × (100 ÷ 100 + Discount Percentage)
D. Original Price = Discounted Price × (Discount Percentage ÷ 100)