A manager invests $400,000 in a technology that should reduce the overall costs of production. The company managed to reduce their cost per unit from $2 to $1.85. After the investment has been made, the $400,000 investment is a. ​Considered a loss b. ​Considered sunk costs, not relevant in further decision making c. ​Considered sunk costs, but still relevant in further decision making d. ​Considered a profit