Answer:
A) No gain or loss on the exchange with Bob, and $12,000 gain on the subsequent sale
Step-by-step explanation:
Since apparently both Bob and Charles owned their property for more than 2 years, the exchange classifies under section 1031 exchange between related parties. Therefore, no gain or loss should be recognized by any of them.
When Charles sold the property to his business associate, who is not related to him, he realize a $12,000 gain (= $312,00 - $300,000 basis).