The correct answer would be: related to his field.
When Tiger Woods promotes products like Nike shoes and Gatorade, he is appealing to the audience's ethos by aligning himself with products that are related to his field, which is professional golf. Tiger Woods is a highly successful and well-known golfer, and his endorsement of products within the field of sports and athletics adds credibility and expertise to the brands he promotes. This connection between Tiger Woods, as a respected figure in the world of golf, and the products he endorses helps to establish trust and appeal to the audience's ethos.