Answer:
The answer is "the increase in welfare in both countries that result from specialization and trade".
Explanation:
Commercial gains imply benefits that are benefitted by specialization and division of work from various countries participating in international trade.
Its profits of trade are the positive benefits of trade instead of creating, meaning as advantage benefits via trade rather than producing advantage oneself.
The whole form of profit is usually called gain. Those gains are indeed the advantages of shifting production factors.
Static trade gains:
