Ken, a calendar-year taxpayer, owns 50 shares of Copper Corporation stock, which was purchased two years ago for $30,000. Oliver sells all 50 shares on December 31, of the current year (2019), for $20,000 and on January 15 (2020), of the following year, purchases 25 shares of Copper Corporation stock. Oliver's recognized loss will be

A) $0

B) $5,000.

C) $7,500.

D) $10,000.