Alieia Boat Company manufactures 10 luxury yachts per month. A navigation system is included in each yacht. Alieia Boat manufactures the navigation system in-house but is considering the possibility of outsourcing this function. At present, the variable cost per unit is $300, and the fixed costs are $38,000 per month. If it outsources the security system, fixed costs could be reduced by half, and the vacant facilities could be rented out to earn $3000 per month of rental income. What is the maximum contract cost that Alieia should pay for outsourcing?

A. any cost lower than $2500 per unit

B. any cost lower than $2200 per unit

C. any cost lower than $300 per unit

D. any cost lower than $3800 per unit