A PLC has non-current assets valued at historic cost of 10 million and the current climate means that the business has become unprofitable. The non-current assets could be sold for 5 million (net of disposal costs). The net present value of future cash flows discounted at the company's weighted average cost of capital (WACC) is 6 million. How much impairment would be charged following the impairment review?

a. 4 million b. 5 million c. None d. 6 million