On January 1, 2015, Blue Inc. purchased a patent for $23,800. Legal fees paid in this purchase amounted to $1,200. The legal remaining life of the patent is 14 years, but Blue believes it will only help increase sales for the next 10 years. On January 1, 2018, Blue was sued for patent infringement and had to spend $3,500 of legal fees in the successful defense of this patent. What is the book value of this patent on December 31, 2018?

A. $14,000

B. $15,000

C. $17,500

D. $18,000

E. $21,600

Please select the correct letter choice.