(b) You have chosen incorrectly. This statement is true.

Restitution allows a plaintiff to recover the amount by which the defendant has been unjustly enriched. Although the boat was only really worth $10,000, A managed to sell the boat for $2,000 more than this, and the result is that A was enriched by $12,000.

B can recover this amount in restitution, which is a better alternative than a claim of $10,000 as compensatory damages.