The correct answer is B) low prices.
One of the main advantages of a big-box retailer is low prices,
People call a big-box retailer to the big retailer’s store that is built in a large space and offers all kind of products for the consumer. It looks like a big box. Because is so large and sells many products and large volumes these retail stores have scale economies that allow them to offer very competitive prices. The high volume of sales, the profit margin of products is lower. This allows the store to offer low prices.