Answer: Option 'D' is correct.
Step-by-step explanation:
Let the original price of computer be p.
Store A advertises that he compute is on sale for 25% off the original price.
Amount of discount would be

So, Price after discount becomes

Store B advertises that it is reducing the computer's price by $180.
So, Price after reduction becomes,

According to question, she concludes that the sale prices are equal,
So, our equation becomes,

Hence, Option 'D' is correct.