An Imperfectly Competitive Firm Produces Two Products (A and B)

An imperfectly competitive firm produces two products (A and B) with interrelated demand functions. If the firm increases the number of units of A sold from 150 to 151, total revenue from the sale of A will increase from $1,500 to $1,505. Taking into account the interdependence between A and B, the marginal revenue from the sale of one additional unit of A must be

A) $5.
B) greater than $5.
C) less than $5.
D) This question cannot be answered without additional information.