Firm A purchased Firm B for $4,000 when B's total owners' equity was $2,000. Firm A completed the qualitative test for goodwill impairment and determined that it is more likely than not that goodwill may be impaired. B had one asset worth $500 more than the book value. One year after the purchase, Firm B's total market value had dropped to $3,200 and the market value of its net identifiable assets was $2,000. What amount of goodwill impairment loss is recorded?
A. $0
B. $800
C. $400
D. $300