On June 1, two years ago, Alex bought 500 shares of Abacus Inc. for $50 per share. On December 15, last year, he sold 400 of these shares for $42 per share and acquired all 400 of the shares back again on January 7 of the current year, for $40 per share. On October 5, of the current year, Alex sold all the Abacus Inc. shares for $45 per share. Which one of the following is Alex's capital gain or loss for the current year? A. Capital gain of $1,500 B. Capital gain of $4,700 C. Capital loss of $1,700 D. Capital loss of $2,500