A student chooses to begin a two-year apprenticeship, during which she will receive $10\,000$ each year. Once this has finished, she expects to earn $25\,000$ per year. Instead of doing the apprenticeship, she could accept an unskilled job that pays $16\,000$ per year. What is the opportunity cost over the two years spent completing the apprenticeship?
- A$10\,000$
- B$12\,000$
- C$25\,000$
- D$32\,000$